Back Up lights

[Degerb]

I need a little electrical help...My back up lights in my 1990 TC do not work. I have continuity between both poles of the socket, regardless of the position of the gearshift  but 0 voltage showing, the fuse is OK. In checking my service manual engine compartment side shield wiring diagram, it shows a backup lamp relay located on the RH front fender well. My car does not have this relay as shown nor can I find one listed in my parts book. I also checked archived posts and found a reference on Mar30, 2004 referencing the relay and success in cleaning the contacts. Has anyone else had this problem? I think probably a dead short could cause the continuity but that to me doesn't explain the good fuse with everything else tied to the circuit working properly.

[Hemi Dude]

You DO INDEED have a backup light relay and it is mounted right on top of the ETAX CONTROLLER where you thought it was supposed to be, on the RH front fender well. That is the computer for your transmission, there are 2 relays next to one another. One is the Backup light relay and the other is the ETAX shut down relay. The Backup lamp relay part number is listed as 5234259. It may be superseded today, but this number should get you to the current number if it has changed.

[Degerb]

Thanks Hemi... I was remiss in neglecting to state I have the Turbo 2.2 with the 6 speed Getrag transmission. The only relay I can see in that position is I think something called a MAPP relay for the turbo. I  can post a picture if you like. The relay I have is # 5227352 and bracket # 5234627. Is it possible the 6 speed and automatic have different locations for the BUP relay?

[Digger914]

15 hours ago, Degerb said:

I need a little electrical help...My back up lights in my 1990 TC do not work. I have continuity between both poles of the socket, regardless of the position of the gearshift  but 0 voltage showing, the fuse is OK. In checking my service manual engine compartment side shield wiring diagram, it shows a backup lamp relay located on the RH front fender well. My car does not have this relay as shown nor can I find one listed in my parts book. I also checked archived posts and found a reference on Mar30, 2004 referencing the relay and success in cleaning the contacts. Has anyone else had this problem? I think probably a dead short could cause the continuity but that to me doesn't explain the good fuse with everything else tied to the circuit working properly.

There isn't much resistance across a relay coil and a VOM set at 20K can make the impedance of the coil look like a dead short. Put your meter on the tranny switch contacts and make sure they open and close when you shift in and out of reverse, If that's good use something to short the pins of the tranny plug connect together and that will tell you if you have loose plug connect, or a problem farther down the line.

[Degerb]

Thanks Digger... One question.. do I need to remove the console to access the switch? 

[Hemi Dude]

16 minutes ago, Degerb said:

One question.. do I need to remove the console to access the switch? 

The backup lamp switch is on the Getrag transaxle itself. in the area of the shift levers. 

[Degerb]

Thanks guys for your input... I think I'll forgo the tranny SW troubleshooting until the weather cools a bit! I still need to know the location of my elusive BUP lamp relay though, it troubles me not knowing where something is located!

[Hemi Dude]

On July 24, 2016 at 8:20 PM, Degerb said:

Thanks guys for your input... I think I'll forgo the tranny SW troubleshooting until the weather cools a bit! I still need to know the location of my elusive BUP lamp relay though, it troubles me not knowing where something is located!

There is NO relay for the 5 speed Getrag transaxle cars. Just the little 2 contact switch screwed into the shifter housing part of the trans.

[Degerb]

Thanks Hemi... that eliminates one source of the problem. In re checking the continuity of the Lamp assy contacts both poles show continuity to ground as well as to each other. That being said there is no voltage either. That leads me to believe the wire bundle is damaged somewhere, as I thing Digger stated probably near or on the tranny. That still however, doesn't explain to me why the fuse didn't blow.... Oh well, check and eliminate one problem at a time!

[Digger914]

I sent you to the tranny connect and switch because I remembered your posting on tranny trouble. Most likely place to find the problem, if the lights worked before you worked on the tranny.

 

Not being the original owner there is the possibility that you're not the first person to work on this problem and someone else might have resolved this problem by cutting the power wire before you got the car. Wouldn't be the first time somebody didn't want to spend money to fix something they didn't need

 

Don't know if you're using a volt meter or tone tester to check for continuity, but you have what sounds like a short. Depending on how you're checking you could be reading continuity through the other bulb filament, they do parallel.

 

As it sounds like you have a short and you have no power and you're not blowing fuses, keep in mind that you're not the first person under the hood 

 

There is a relay involved here, if there wasn't your back up lights would be on anytime the tranny was in reverse, key on or not. so don't forget to turn the key on, before you look for power. As things do happen look for a cut wire anyplace after power distribution to the fuse panel, under the hood and other places where the harness is easy to get at. After you find power, look close at the harness in the rear where it makes a couple of tight turns as that's where the cables usually go bad first.

[Degerb]

Thanks Digger... I don't really know if the lights ever workedI  I have had the car since April and with the tranny issues. I just never looked for something like  a backup light issue. I have a pair of ramps on order so I can access the BUP switch as a start. I don't really like jack stands, paranoia I guess. I'm much more cautious now, than when I was a young buck!  I guess on the bright side it's a good thing that what I have, it isn't an intermittent short!

[Hemi Dude]

17 hours ago, Digger914 said:

I sent you to the tranny connect and switch because I remembered your posting on tranny trouble. Most likely place to find the problem, if the lights worked before you worked on the tranny.

 

Not being the original owner there is the possibility that you're not the first person to work on this problem and someone else might have resolved this problem by cutting the power wire before you got the car. Wouldn't be the first time somebody didn't want to spend money to fix something they didn't need

 

Don't know if you're using a volt meter or tone tester to check for continuity, but you have what sounds like a short. Depending on how you're checking you could be reading continuity through the other bulb filament, they do parallel.

 

As it sounds like you have a short and you have no power and you're not blowing fuses, keep in mind that you're not the first person under the hood 

 

There is a relay involved here, if there wasn't your back up lights would be on anytime the tranny was in reverse, key on or not. so don't forget to turn the key on, before you look for power. As things do happen look for a cut wire anyplace after power distribution to the fuse panel, under the hood and other places where the harness is easy to get at. After you find power, look close at the harness in the rear where it makes a couple of tight turns as that's where the cables usually go bad first.

I guess there will always be a debate as to who gives the correct advice here. My source for this information is the RED 90 - 91 Chrysler Shop Manual.

So, ONE LAST TIME. THERE IS NO RELAY INVOLVED IN THIS particular CIRCUIT!        Power (12 Volts) to the backup light circuit begins at the IGNITION SWITCH, the A2 RUN CIRCUIT.

THIS CIRCUIT IS ONLY HOT WHEN THE IGNITION SWITCH IS IN THE RUN POSITION! Power (12 Volts) passes to and through FUSE #2 as the B1 circuit, then through bulkhead connector #27 (under the dash) and into the engine compartment directly to the BACKUP LIGHT SWITCH mounted on the transaxle. (in this case, with the Getrag 5 speed, there is NO NEED for a relay as mentioned previously)  That means that there should always be 12 Volts at the backup light switch terminal B1 18 White WHEN THE IGNITION SWITCH IS IN THE RUN POSITION unless FUSE #2 is blown.
When the transaxle is shifted into reverse, with the ignition switch ON, connection is made at the backup light switch and the power continues from the switch as circuit B2 18 Violet through bulkhead connector terminal #28 (under the dash). The power is now inside the cabin of the automobile. The conductor (wire) remains B2 18 Violet as it continues down the drivers side kick panel area to a connector and then along the inside of the left side rocker panel to the trunk area. Here it joins a 3 way connector in an access hole above the wheelhouse. From there the circuit splits to 2 similar 18 Violet conductors and proceeds to the right and left backup light bulbs. POWER NOW PASSES THROUGH THE FILAMENT of the bulbs and exits into the  X2 18 gray conductor which returns to the same 3 way connector in the LEFT ACCESS HOLE ABOVE THE WHEELHOUSE, then on to a splice where it joins with all the other GROUNDING conductors (wires) and then to a GROUNDED TERMINAL screwed to the body of the car.

 

A lesson between SHORT and OPEN CIRCUIT.       A short will blow a fuse, burn a wire or component and possibly cause a fire.       

                                                                                      An OPEN circuit will cause NOTHING to function in the circuit it is related to, that's all. 

[Digger914]

On ‎7‎/‎28‎/‎2016 at 10:23 AM, Hemi Dude said:

I guess there will always be a debate as to who gives the correct advice here. My source for this information is the RED 90 - 91 Chrysler Shop Manual.

So, ONE LAST TIME. THERE IS NO RELAY INVOLVED IN THIS particular CIRCUIT!        Power (12 Volts) to the backup light circuit begins at the IGNITION SWITCH, the A2 RUN CIRCUIT.

THIS CIRCUIT IS ONLY HOT WHEN THE IGNITION SWITCH IS IN THE RUN POSITION! Power (12 Volts) passes to and through FUSE #2 as the B1 circuit, then through bulkhead connector #27 (under the dash) and into the engine compartment directly to the BACKUP LIGHT SWITCH mounted on the transaxle. (in this case, with the Getrag 5 speed, there is NO NEED for a relay as mentioned previously)  That means that there should always be 12 Volts at the backup light switch terminal B1 18 White WHEN THE IGNITION SWITCH IS IN THE RUN POSITION unless FUSE #2 is blown.
When the transaxle is shifted into reverse, with the ignition switch ON, connection is made at the backup light switch and the power continues from the switch as circuit B2 18 Violet through bulkhead connector terminal #28 (under the dash). The power is now inside the cabin of the automobile. The conductor (wire) remains B2 18 Violet as it continues down the drivers side kick panel area to a connector and then along the inside of the left side rocker panel to the trunk area. Here it joins a 3 way connector in an access hole above the wheelhouse. From there the circuit splits to 2 similar 18 Violet conductors and proceeds to the right and left backup light bulbs. POWER NOW PASSES THROUGH THE FILAMENT of the bulbs and exits into the  X2 18 gray conductor which returns to the same 3 way connector in the LEFT ACCESS HOLE ABOVE THE WHEELHOUSE, then on to a splice where it joins with all the other GROUNDING conductors (wires) and then to a GROUNDED TERMINAL screwed to the body of the car.

 

A lesson between SHORT and OPEN CIRCUIT.       A short will blow a fuse, burn a wire or component and possibly cause a fire.       

                                                                                      An OPEN circuit will cause NOTHING to function in the circuit it is related to, that's all. 

I stand corrected ------------   "I don't often interject myself here any more as there are others who think they know everything, so I just read and often laugh. That being said, you DO INDEED have a backup light relay and it is mounted right on top of the ETAX CONTROLLER"      

----------  Again.

 

I must be working from the wrong "Red Manual" as near as I can tell, every relay in the car is somehow powered by turning the key ON. If it weren't for relays this tiny little wire would be a quarter inch thick. I suppose if it was really important, I could look and make sure, but "There is a relay involved here" was a joke son, a joke.

 

Obviously it's important for your to be the correct advice giver here and it's no skin off my teeth either way, so the forum is yours Dude. Enjoy.

[Hemi Dude]

2 hours ago, Digger914 said:

I stand corrected ------------   "I don't often interject myself here any more as there are others who think they know everything, so I just read and often laugh. That being said, you DO INDEED have a backup light relay and it is mounted right on top of the ETAX CONTROLLER"      

----------  Again.

 

I must be working from the wrong "Red Manual" as near as I can tell, every relay in the car is somehow powered by turning the key ON. If it weren't for relays this tiny little wire would be a quarter inch thick. I suppose if it was really important, I could look and make sure, but "There is a relay involved here" was a joke son, a joke.

 

Obviously it's important for your to be the correct advice giver here and it's no skin off my teeth either way, so the forum is yours Dude. Enjoy.

May I say, for the record, that when this issue was first brought up, Degerb wrote the following, "My car does not have this relay as shown nor can I find one listed in my parts book."

I know it was foolish of me to "ASSUME" that his car has the 41TE transaxle, just because most 1990 TCs have that. Degerb did correct that in a followup. So now we all know that his is the Getrag transaxle.  

The most important criteria of this forum is to provide information to those who ask THAT IS AS CORRECT AS POSSIBLE.  Digger, you wrote "I suppose if it was really important, I could look and make sure, but "There is a relay involved here" was a joke son, a joke."   Do you suppose that the readers should all be led to believe that there is a relay in this circuit when there is NOT?

You give a lot of valuable advice here Digger, I have seen that, so don't get your back up and write foolish stuff. "Obviously it's important for your to be the correct advice giver here" It is beneath you.

We are here to provide CORRECT information, PERIOD!        Degerb, I have provided a photo of the Getrag transaxle, you can see the 2 terminal backup light switch right below the shift linkage.

For those of you who may be interested, you can see where the DISTANCE SENSOR is located. It is also unique to this application.

[Degerb]

I appreciate both of your insights on my BUP problem. Your picture is like an old saying.... A picture is worth a thousand words! It's now up to me to start tracing the wire bundle to find the problem. It will be interesting to find the culprit. It's not like a backup light is a safety item but It just bugs me the heck out of me when something doesn't work as advertised!

[Nile]

Degerb  -  I recently had the same issue with my 90 16v.  The problem was the switch.  Luckily, I had a spare, because the local auto parts stores all had switches they said were correct, but didn't look like mine (threads were too short) and didn't work.  By the way, loosening the switch from the tranny was a BEAR!  It was easy enough to get at, but required a pipe over the breaker bar to get sufficient leverage.  My advice would be to take your old switch out and bring it with you to any parts stores to make sure the new one matches yours EXACTLY, because they are sometimes reluctant to take back electrical parts.  Another option might be Rock Auto, but again, I'd want to make sure the replacement was an exact match.  

[Degerb]

Thanks Nile for the heads up! I'll be sure to have a cheater bar for sure....It's  good to know about the auto parts store BUP switches. I found a NOS switch available but very pricey!

[Jim HIlgeford]

Arizona Parts has the switch in stock.