Diagnosis and Repair Issues Concerning Your Imperial's Taillights


Imperial Home Page -> Repair -> Electrical System -> Taillights

Question from Dave:

What will cause poor brake lights apart from a bad ground. Mine seem to be sometimes working, but dull. However when you rev the engine they go bright! The switch is a new one, & the wires when touched together light the lights great. would the wires crossed to the switch over give this effect?

I have swapped the battery, still no change.This can only , with my method of thinking leave a Hydraulic fault. I have ruled out the electrical circuit from the B/L switch too.

When you press the brake pedal the lights will brighten after about 5 to 10 seconds. I am wondering if the new master cylinder is playing up or starting too.


From Paul:

If the stop lights work great when you bypass the switch, then there is something wrong with the switch. In the case of this car, it could also be that there is something wrong with the hydraulics, or the switch could be clogged. How is your brake fluid?

When you rebuilt the brakes, did you up grade the master cylinder to a newer model? If not, then we are still talking about the fluid activated switch on the base of your master cylinder.

It would probably be a good idea to have another new switch on hand before removing the old one. If a particle lodged into the old switch, and it is partially clogged, cleaning it out may be more difficult that simply replacing it.

This problem is not uncommon. Oil pressure sending units work similarly to this particular switch. They also can provide incorrect readings due to blockages.

The part I don't get here is that it was said that the lights brightened up with a rev of the engine. When the switch is beginning to fail, usually the stop lights will either take more pressure than is necessary to stop the car to work, or it will fail completely. In any case, engine RPMs should not have an effect. I suppose that an imperfect connection within the switch could be strengthened with a brief electrical surge, but that seems a little far fetched. The connectors on the end of the switch could be suspect and may need cleaning. This could be done with a small piece of emery paper, and may not require pulling the switch.

From Patrick:

I had similar symptoms once with my '70. I tried everything. I was complaining about it at a party, worried that I wouldn't pass my next brake inspection. A fellow there who turned out to be a very experienced mechanic went out to the car, pulled the bulbs and wiped out the sockets brisquely with his handcerchief. Then he rubbed the light posts and put it all back together. Problem solved. It was a bad ground.

From Tony:

I, too, experienced the exact same situation with my '66 LeBaron, except my circumstances were a little more extreme-massive corrosion in the bulb sockets. This was due to the car being submerged for two hours, after a through cleaning they function again. I would try cleaning your 67s sockets out coupled with cleaning or replacing your bulbs first; then troubleshoot more in depth if the problem persists.

From John:

Corrosion of the sockets is a very common problem. On the '67 or other years with multiple bulbs, you may also have some incorrect bulbs, since they are not all the same bulb number. If this car is new to you, that is worth confirming also. Most newer cars put a special grease in the bulb sockets to avoid the corrosion problem.

Question from Rob:

I'm trying to chase a problem in the taillights of a "lesser" Mopar. They won't stay on. The problem appears to be on the passenger side. The wiring goes from the passenger side to the driver's. If I pull the bulb out, clean and wiggle it and put it back in they both will light up. The problem is that as soon as you use the bulbs for any other reason, such as blinkers, it goes out and will not go back on. Could this be a coincidence? The hazards, blinkers and brake lights all appear to work normally at all times.

I assume Imperials could experience the same problems.


From Chris:

Sounds like a bad socket. Wiggling it (presumably while the tail lamps are on) allows you to make contact (and once made, it arcs for as long as the circuit is closed, meaning as long as that filament stays lit), but the moment the lamp goes out, the contact cannot be reestablished unless you wiggle it again. That's because the current isn't able to create the arc from the get-go, only maintain it once the circuit is established.

What happens when you use the other filament (the bright one, which serves the brake lamp, signal and hazard flasher) is that the dim filament (which serves the tail lamp only) naturally goes out. It's just how some cars are wired... so using the brakes or signals is the same as turning off the tail lamps. (You can verify this by watching the functioning bulb on the other side of the car... you should see that the filaments "alternate" if you use the signal with the tail lamps on.)

See if the socket is rusty or misshapen, or if the contacts at the bottom of the socket are damaged, dirty or out of place (or missing the spring at the bottom). You'll probably solve your problem there...

From John:

I've experienced this problem a few times & received some advice from another Imperial owner that had the same problems. The problem is either poor contact of the bulb to the socket & or poor ground of the socket. Remove the bulb from the affected socket & clean up the contacts with steel wool or very fine emery cloth. If the socket is the type that pops out of the light assembly, do the same thing to the area where is makes contact to the assembly. This should cure your problems. You may have noticed on some newer vehicles that a conductive grease is used in the bulb sockets. You may want to try that to keep any corrosion from returning.

From Roger:

I don't know the type of car you are working on. It sounds like the lights have a common problem and it is the ground. Most tail light systems use the three wires. It should have power to right turn, left turn, and tail light with no ground wire. The system ground is through the body of the car and brake light are through the turn signals. The tail light assembly bolts to the body and the light pig tails are isolated. When you remove the light bulb does the other side go out? If so the other side is the non-grounded side. Other things to check is the bulb itself. If the brake light filament is broken and touching the tail light filament, it creates a electrical system by pass into another circuit. This will create strange behavior in the system. Electrical power is like water. It takes the path of least resistance. It flows to ground. If the ground is not in the same area of the circuit it will flow to the area that has ground. If this happens two circuits can be energized at the same time. Fix the ground and you fix the problem. A test light can show system feed back.

Question from (1956):

I have the backup lights on my '56 on all the time presumably due to the malfunction of the backup light switch on the PowerFlite transmission. My question is: is this switch identical to the brake light switch? I know there has been reports of the brake light switch malfunctioning also.

Reply from Paul:

This should be easy enough to fix. I believe that the switch is located in the dash around the area of the push buttons. I haven't had the '56 apart, but I have worked on it in my '60 LeBaron.

Question from Dave (1958):

My brake lights do not work on a '58 I recently acquired.. I found a wire disconnected at the bottom of the master cylinder sensor/pressure switch.There is another wire that is bundled with the one that I connected that doesn't have a connector. The one that I connected had a female connector so it was obvious where it went.. Is there two wires that go to that sensor?
I have a hard time seeing because it's under the PB bellows...


From Paul:

Two wires go to the brake light switch. If I remember correctly, it doesn't matter which way they go.

From Hugh:

There should be both a male and female connector on the brake light switch. You will need a replacement. Here is a part number: Brake Light Switch - NAPA SL136

This is correct only up to a point. There may be an absolutely correct part available. This part will work very well, but will need an adaptor. The part has a 1/8 inch pipe thread and the bottom of the master cylinder is 1/4 inch. However, an adaptor is readily available, also from NAPA, and barely affects appearance. All you will see is an additional 5/8 inch hexagonal nut. A very small price to pay for being able to get the part over the shelf.

Question from Hugh (1958):

I cannot recall how to change the license plate bulb on my 58. I'm sure I have done it before. I was just down on my hands and knees looking at it but just cannot see how to access it. I'd appreciate some help.


From Bill:

I don't know how close the bulb placement is in the 1958 compared to the 1959. I know the bumpers are different, and my '59 had some type of clear plastic dome type cover that was broken off, and just kind of lodged in there when I got it, so I took it off and left it off. I have replaced my bulb several times, since I was using the wrong voltage, and the easiest way to do it is lie on your back looking up at the bulb, and put it in from there. If you try to do it from above it will be next to impossible. I'm just not looking forward to having to get inside the fins to unscrew the bolts to someday change the tail light bulbs when they burn out. I have my shiny new bullets from oldcarlens.com, but have not put them on yet because of this.

From Doug:

According to my '58 Imperial repair manual. The taillight bulbs are on a plug in/pull out type socket that doesn't require the removal of any bolts. It is however necessary to remove several bolts if you are intending to remove the entire taillight assembly. I don't think that this design was significantly altered on the '59s which used the exact '57-'58 body with some different trim.

Question from Bill (1959):

I was wondering if anyone knew where to find the gaskets for 1959 Imperial back up lenses, or is this a part I will have to manufacture? I've got new lenses, but they always have condensation inside. I posted this to the list last night, but didn't see it here, so I'm trying once again.


From Arran:

Take one of the old ones to use as a pattern, find some rubber of appropriate thickness, and cut out some yourself. You could find a pair of ready made ones but I doubt whether they would be cheaper or better then a home made pair. One thing that you will need is to either make or borrow a hole punch for the screw holes.

From Roger:

I have made lots of gaskets with cereal boxes. Lay your lens on the cardboard and trace. Mark screw holes with pencil find a small socket and use it to tap on to cut holes for screws then use box cutter to trim cereal box. If you take your time it will be like the original.

Question from Bill (1959):

My tail lights won't go off. They stay lit, but dimmer than the regular setting, so I have to pull the battery cable every  time I park. Anyone have any ideas on the tail lights?


From Timothy:

I know that this sounds weird but... if it is only the taillights and nothing else that is lighting up. Your problem is quite possibly with the brakes. The brake light switch on my sixty, and presumably the 59's too, is a pressure active switch that screws into the under side of the master cylinder. If that is the problem, it means either that the switch is bad (which seems unlikely to me but who knows ((if it is toast, you can probably get one from Andy Bernbaum)) or that for some reason that there is more pressure in your brake lines than there should be when they are at rest. I hope that that helps. Oh and to test it I'd just carefully disconnect the wire(s) on the brake light switch, reconnect the battery and see if the taillights are still on.

Follow-up from Roger:

Tail lights are different than brake lights. If the latter, the switch is a likely culprit. If the former...?

From Steve:

There is no connection to the brake lights on the '59 gear selector. There is a switch on the side of the unit but that is for the back-up lights. On the brake light problem I would pull the wires off the brake switch and see if they go out. If they do then check the resistance of the switch or simply replace it. You can get a close match at NAPA or a NOS switch from Andy Bernbaum.

From John:

Somehow, this sounds like it could be a poor ground problem if it isn't the brake light switch.

Question from Buck (1962):

I have a bad tail light. While checking to see what kind of bulb I would need to replace I found out that some time in the past some one had glued the lens in. They did a darn good job because it wasn't noticeable at all. When I put it back together the lens no longer sits right. Kind of crooked. I have already sent away for and received a set of complete taillights from Lowell Howe (A GREAT guy).

Question 1: Would it be easier to replace insides or the whole taillight? I would rather keep mine because they look slightly better than the ones I bought. 

Question 2: Would it involve wire cutting and splicing to replace the innards?

ANY comments and suggestions are always welcome.

Reply from Kerry

Haven't gotten into my 62's taillights yet but EVERY other car I've messed with had connectors on the wires going to the taillights so no splicing was necessary. This includes '61 Imps so it's a pretty sure bet the '62 has connectors also. Of course, Lowell Howe may have just snipped them off when he removed them from the parts car in which case you can install new ones. I would NOT recommend hard wiring into the main harness. Spade lug connectors are cheap and available at any parts store in both solder on and crimp on style. You can get a blister pack of male/female connectors for a couple bucks.

Question from Gary (1966):

I am trying to get my back-up lights to work; they light up when I shift from reverse to park but wont stay on in reverse. I have located the switch (under the steering column) and I do not know how to adjust it or do I have to replace it.


From Kent:

Some switches are adjusted by placing a small gauge drill bit, usually marked numerically not necessarily fractions, such as a #43 drill bit size for example, in the B/U switches adjusting hole. You generally place the shift lever in Park or Neutral, place the drill bit in the adjusting hole until it sets a predetermined depth, once the drill bit has seated properly, secure the B/U light switch. Some B/U switches on the columns are loosely mounted and slide to adjust, you place the shift lever in park or neutral, shift to reverse, check B/U lights, and if ok secure the switch.

From Dick:

Slightly loosen the mounting screws which hold the switch to the steering column, then turn on the key and have an accomplice with a loud voice stand behind the car.

Put the shift lever in "R" and then slide the switch clockwise or counter-clockwise around the column, taking advantage of the slightly oversized mounting holes.

When your compadre sings out "THEY'RE ON!", tighten the screws and Bob's your uncle.

No Reverse Lights (1967):

Before you start troubleshooting, make sure there is no other problem by crossing the two leads on the female half of the switch connector. With ignition on the back up lights should come on. Running a light bulb from the one of back up lights to where you are under the dash is a great idea unless you have a buddy with infinite patience who will stand behind your car. I tried unsucessfully several times to get the lights to work with the existing switch . I would set it up with the #42 drill as noted in the service manual but after a bit of adjustment I would hear the "snap" of the lever disengaging . Prying up the metal collar as suggested by Leo should work as well but trying to do it with a mirror in reverse seemed beyond me. Extending the lever seemed easier. I took an old hollow plastic air mattress plug ,drilled it out {not too much} and fit it over the plastic lever extending it by about a 1/4 inch. You don't need to glue it but have it long enough to cover most of the lever. This extension allows for shifting the switch collar, now sitting a bit higher on the steering column with the slotted holes to easily "match" the lights coming on with car in reverse gear. The extra 1/4 inch makes a big difference as the switch lever now stays in the slot ! Car also kicks emergency brake off when shifted into drive like it's supposed to.

Paul Whyte

Question from Carl (1967):

I own a '67 CC & have traced my inoperative brake lights to the turn signal switch in the tilt column. (&^^*%#%). However, I've run across one more item that could possibly change that theory.

If memory serves (after many years), I seem to recall that the power windows work only with the ign/acc "on". Do the power windows on a '67 work directly from the battery or only when the "acc" or ignition is on? (I know that the '57s worked off the battery, but did the '67s?)

My windows activiate regardless of the ignition, so I'm wondering if the wiring could have been 'boogered' with...changing the diagnosis altogether?


From Donald:

'67 was last year for windows powered all the time. In '68 they were wired thru Ignition swith.

From Tim:

On my '67 Crown hardtop, the power windows work without the ignition being turned on.

Should you end up needing to replace your turn signal switch, you can get a good quality new one from these folks:
They can sell you a cancel cam too -- which you might as well replace while you're at it, whether it needs it (yet!) or not.

From Joe:

Just replaced the turn signal switch on my '67 Crown Coupe for the same reason. Trust me, after 22 years with Chrysler Corp. as a field tech rep. this is a common occurrence, not only on the early cars, but right up through the mid '80's. Mitchells in Fairmount, Ga. was kind enough to sell me a NOS switch for the low price of $169.95.

Brake lights work fine now...

All the power stuff (windows, seats, etc.) work without the switch on. Chrysler changed this in '68. The switch is a booger to change especially if you've got tilt -tel.

Question from Anthony (1967):

When you step on the brakes ---dash lights and running lights and turn signal fender lights up! Has anyone experienced this sort of problem before! I am visiting my mechanic again tomorrow---he is thinking there is some sort of grounding problem some where! Initially, he thought it may be a faulty turn signal switch---however----when the car is off and you depress the brakes, that is when the dash and running lights illuminate.


From Brad:

This is a very common issue with an easy solution. There may be a shorted bulb or pigtail probably in the Stop/Tail combo cct. Replace the bulbs in the rear of the car for starters then if that doesn't work, test all pigtails for continuity/shorts.

From James:

Have you checked your fuses? I had a blown fuse on my 76 that caused the dome light to come on when I pressed the brake pedal. It caused me much confusion too, hehe!

From Craig:

This sound like a bad ground at the tail lights. I have chased these a couple of times in the past. If your brake lights are dim it's the ground. If they are bright it's Brad's short.

Reply from John:

The tail lights should be evenly bright when not stepping on the brake. If any are too bright, you may have the wrong bulbs in some of them.

From John:

I'd start by checking all fuses. I've had strange lighting situations with a blown fuse in a '63. I would also check for pinched wires to tail lights & any wires near the brake pedal. Have you recently replaced any bulbs? If yes, are you sure they are the correct type? Is the turn signal switch a generic replacement or Mopar & is it wired correctly?

From Peter:

I agree with Craig, sounds like a ground problem.

Question from Mark (1968):

I am trying to get all the bulbs in the taillights of my '68 convertible to match, in terms of brightness. There are 6 bulbs in all; the 4 on the outside are dual filament (I think they're 1157s)-- when you just have the lights on only 1 filament is lit; when you apply the brakes, both filaments light up, doubling the brightness.

Well, on my convertible, the brightness of the inner 2 bulbs is equal to the other 4 when you have the brakes on-- in other words, too bright. On my 4 dr. hardtop, they are all equal brightness.

I checked the inner 2 on the 4 dr., and it's a 1095. That number is in some GE and Sylvania parts books, but no one around here carries them, and there is no superceding number that anyone can find.

These are single filament, listed as .51 amps (or watts). I can't find anything close to that.

Some books call for 1134s, but I think that's what I have in my convertible, which are too bright.

Anybody have a good part# and a source to buy?


From Kerry:

Not clear to me if the bulbs are the same or not. If they are, swap them and see if the brightness stays with the bulb or the socket. I'm betting your ground is weak on the dimmer bulbs. Clean up the socket and be sure you have a good solid ground and see if that makes a difference.

From Dick:

I found 1095s in stock at my local NAPA store.

In a 68, the inner two tail light bulbs are just that, tail light only, thus the single filament. The outer two main bulbs are stop/turn lights also, in addition to the tail light function, so they are indeed 1157s. The marker lights are of course on only with the tail lights, and have single filaments also.

Those fortunate few of us who enjoy owning the beautiful 67s get to enjoy all 6 rear main bulbs functioning as tail AND stop lights, bringing a dazzling red glow to the neighborhood areas which are fortunate to be able to admire the beautiful 1967 rear ends.

The two 1157s on each side light the 6 watt filament for tail lights, and the 32 watt filament for brake/turn lights. When the 32 watt filament is on, you cannot tell whether or not the 6 watt filament is on, because the light difference is very small.

The inner two bulbs, to have the same brightness as the outer ones when only the tail lights are on have to be 6 watt filament bulbs also.

In this case the second filament is not used (on the 68s) so a two filament bulb is not required in the center two positions.

Putting a two filament bulb into a single contact socket will usually result in both filaments lighting (depending on the particular position of the contact button in the socket) which is probably what is wrong with Mark's car.

The 1034 is the older version of the 1157. The specs are nearly identical - the only difference in the design sheet is that the estimated life of the 32 CP filament in the 1034 is 200 hours, while the same filament in the 1157 is rated at 600 hours.

Now there is an even tougher bulb available, for which I do not have the design specs (it's too new for my data sheets); it is the 2157, again a substitute for both of the above, but much more tolerant of vibration, and much longer life. These are what is used in over-the-road trucks - they are TOUGH!

Mark, I'm sorry the '67 didn't solve your problem entirely to your satisfaction. I take it you didn't try the 89 yet. The original 1095 used an S8 bulb, which placed the center of intensity 1.25 inches up from the contact base, in a 2 inch total height bulb.

The 67 has exactly the same electrical specs as the 1095, including candlepower, but uses a G6 bulb, which places the center of light intensity 13/16 inches up from the contact base, 7/16 of an inch lower than the original 1095. This moves the spot somewhat out of the focus point, apparently, thus the appearance of less intensity when installed in a 68.

The 89 has the same base, but slightly higher candlepower (6 CP instead of 4 CP). The center of intensity is only 1/16 inch higher than the 67, but that plus the higher CP might make a very close match - give that a try and let us know how it works out.

Next time I venture into civilization, I will ask in our NAPA store if they can still obtain the 1095 bulbs out here - if they can, I'll try to order a box. If that works, I'll make them available to members of the club at cost. I last bought them about 1 year ago. Our store has been in business for at least 25 years, so mine might have been old stock.

A 94 would fit, but it is a dual contact bulb (you'd have to change the socket) and it would be much too bright - it is 15 CP. The center of light intensity is also too low. The 93 is also 15 CP, that's why it looked too bright.

Question from HT (1972):

I'm having some sort of problem with the tail lights on my '72 Imp. The brake lights and blinkers work fine. When I pull the light switch all the way on I get some sort of clicking noise (intermittent) from the dash and I do not have tail lights or side marker lights (in front or back). When the light switch is pulled all the way out are you still supposed to have front parking lights on? The bulbs are good although the lower bulbs in front do not illuminate with the turn signal switch on. No lights illuminate when the switch is in the parking light on position. I could definitely use some immediate help / advice.

Reply from Ken:

I believe your head light switch is not working properly, try a new one.  Possibly great lakes NOS, they seem to have a fair amount of parts (NEW PARTS), but there not inexpensive.

Question from Dave (1981):

Even though we got 4 inches of snow yesterday here in Wisconsin, I spent the weekend getting my new 1981 ready for the summer. Noticed that the brake lights don't come on. Fuse, bulbs, turn signals ok.

Is there anything other than the switch mounted on the brake pedal support that could be the problem? Is there a method of checking before removing and replacing?


From David:

My 81 had the same problem. I found two things, one was a broken wire at the switch and second, the switch itself was also bad. I replaced the switch, fixed the wire and all is well.

From Dick:

You can always just jumper across the switch terminal to see if that brings the brake lights on. If it does, you know the problem is right there, either the switch itself is bad, or (more likely), it is just out of adjustment. Make sure that the pedal motion operates the switch so that you can feel or hear the click. If it still doesn't light the brake lights with the terminals bypassed, the problem is going to require someone to take the wiring diagram and test light, and follow the 12 volts from the fuse panel to the switch, then through the turn signal switch (another likely failure point), and finally through the harness connectors to the rear of the car. There is no easy way.

Question from Dave (1981):

I finally have the rebuilt dash and steering column in the car but I have one problem left to fix, I don't know what tail lights go where. I didn't find them in there and I don't have the owners book. What bulbs do I need and where do they go?

Reply from Bill:

There are 10 light bulbs across the rear end of the 1982-83 Imperial. From the outside in :

Side marker lamp (#168) 

Tail/Turn/Stop Lamp (#1157) 

Tail/Turn/Stop Lamp (#1157) 

Tail Lamp (#904) 

Back up Lamp (#1156)

If you lay out the rear wiring across the back of the trunk, you can put the right bulbs in the right spots by following the above from the right rear outside in and then reversing the above order to work your way out to the left outside.

The service manual says the rear cornering bulbs are #1157, but they are the small glass base bulb #168 and not the larger brass base bulb.

The rear wiring/bulbs is under a cover which can be removed by removing the Phillips head screws just inside the lower trunk edge.

You also have two license plate lamps above the license plate. You will need two #168 bulbs. Install them by removing the two screws for each lamp and remove the socket/lens assembly.

This page last updated October 12, 2004.  Send us your feedback, and come join the Imperial Mailing List - Online Car Club