Before you go replacing the CTM or adding a relay, check the wire harnesses around the CTM very carefully. I have only heard of it happening once, but there was a guy on here who had headlight problems too and he had some wires get chafed and cut up on a metal bracket near his CTM. Once he fixed the wiring everything was fine, but he was still out the $200.00 he spent on his new CTM. Here is the thread from his light problem:

https://dodgeforum.com/forum/2nd-gen...t-problem.html

I ran across it while searching for info on new headlight bulbs for my truck. It might be a good idea to go over the wiring at the CTM and the light too very carefully before doing anything else.

If you need it, I can mail you a copy of the service manual on CD. It's too big a file to email, it's 77.8 MB. I poked around on the free download link here, I don't know if it works or not. It looks like a real pain to use, if you ask me. if you want the manual, PM me your name and address and I'll get one out to you.

Jimmy

 

i just located the manual, awesome. I'll check it out as soon as work is over

 

I read the manual and it looks like at the CTM on connector (plug) #1 on pin #11 there should be a purple/white wire there. This should be the negative input to the CTM from the multi-function switch for low beams on. On connector #3 at pin #4 you should have a purple/white wire there that is the 12 volt output to the low beam side of the left headlight.

What you can try first is cut the purple/white wire at pin 4 on connector 3 that is the 12 volt output to the low beam side of the left headlight. Make the cut a couple of inches from the CTM connector, in case you have to reconnect it in the future. Temporarily connect a separate wire to the positive post of the battery through a 20 amp fuse. Connect this wire to the side of the purple/white wire going out to the headlight. If the low beam comes on, then you know the wiring to the light from the CTM is OK.

Leave that wire cut, and test with a voltmeter at the purple/white wire on connector 1 at pin 11 on the CTM. You should have a ground there with the headlamp switch on and the high beams off. Turn the high beams on and you should have nothing on that wire at all. No ground and no positive voltage.

When you have confirmed you have the correct wires, splice a short length of wire about the same gauge as the purple/white wire into the purple/white wire at pin 11 on connector 1. Don't cut it, just skin the insulation back and solder a short length of wire to it and tape it up, or you can use T-Taps or butt connectors. However you do it, this wire needs to stay connected to the CTM so the right headlight will work.

I would say use about a 14 gauge wire for power to the relay. You can use a fuse holder of at or near the same wire gauge, crimp on a ring terminal and connect one end of the fuse holder to the positive post of the battery, or you can use the positive connection at the power distribution center. Then connect the other end of the fuse holder to your power wire and run it through a grommet into the cab of the truck. There is a large rubber grommet on the firewall between the brake booster and the left hood hinge where you can poke a hole and run it through pretty easily. Poke your hole in the inside area of the grommet.

Once you have the power wire in the cab, don't put the fuse in the fuse holder yet. You can get a Bosch 30 amp relay for maybe 5 bucks at any parts store. You can get the power wire and fuse holder there too. Pick up some insulated 1/4" female spade terminals to make your connections on the relay. Crimp them on the ends of the wire and slide them onto the relay terminals.

Put the wire you spliced into the purple/white wire from pin # 11 on connector 1 to terminal 85 on the relay.

Put the purple/white wire from pin #4 on connector 3 to terminal 30 on the relay. You will probably need to use a short pice of wire to extend it to the relay. Use the same gauge wire as the purple/white.

Put the power wire from the battery to both terminals 86 and 87. You can use a short section of a smaller gauge wire and just jump it from 86 to 87.

There is no connection on terminal 87a, but I like to slide a female spade terminal on it anyway to insulate it and avoid any possible problems.

Then put the fuse in the fuse holder. The fuse will protect your new circuit in case there is a problem or there is ever a short to ground in the power wire. With the fuse in place, if there is a problem it will just blow the fuse instead of causing a fire.

When you get this all wired up, the left low beam should turn on with the headlight switch. The only difference is now that low beam is getting its power from an external relay instead of the internal relay in the CTM.

It's also a good idea to wrap electrical tape around the terminals of the relay, so the can't touch other wires, components or metal under the dash. You can also buy a relay socket which has wires on it already to make it easier to make the connections, but not all parts stores will sell a relay socket. Radio Shack probably does though. In fact Radio Shack probably has the relay, wires and female spade terminals too. You need a SPDT (Single Pole Double Throw) relay to make this work.

Once you get it all working, just use wire ties or tape and wire tie the relay and its wiring securely under the dash. You don't want it falling down and getting tangled in your feet while you are driving.

All together, this is probably 20 or 25 bucks in parts. If you can find a used CTM, I have no idea what they would charge you for one. I had a junkyard here in Florida quote me 50 bucks for a used one once. Maybe it's about the same where you live, and if so it might be better to try a used CTM instead of this make-it-work-with-a-relay thing.

But from reading the wire diagram and from what you described so far about the truck, I bet this setup would work just fine. And not to be an *** about it, but I take no responsibility for any problems that arise from this. This is an idea that looks to me like it would work and save you some money.

Let us know what happens.

Jimmy

 

So here is the update:

I bought a TCM (which apparently is also called a CTM (Central Timing Module), BCM (Body Control Module), TCCM, and "that thing by the driver side kick panel"

None were available as used in the entire area, bought a new one for 255, after tax 285. Didn't make any difference... so let me know if anyone needs one, I'll sell it for 200 shipped! Only used for about 15 seconds

We tested a new switch - same issue

We tested a replacement dimmer switch - same issue

And now the passenger side low beam doesn't work, I only have passenger side high beam lights now, and when I "flick" my high beams with the lights off nothing happens.

The dealer mechanic pretty much said the only option now is wiring, so I get to rip the dashboard apart this weekend to see if I can find some wires getting cut apart. He said its not uncommon on the dodge dakotas that have the adjustable steering wheels because the wiring will get pinched in the mechanism.

 

Sorry to hear you are still having trouble with it. I have heard and read on Dakota's with tilt steering the wire harness under the steering column can get chewed up, or there is a plug that gets disconnected or something. I am not familiar with the problem though, my truck doesn't have tilt steering. Seems like I have seen and read posts here about it though, you may find more info if you use the search function. Good luck with it.

Jimmy

 

I found this thread and it defines my problem perfectly....

I need a solution.

Here is how I got there. Driver side light went out.

Replaced bulb and tested... it worked fine. Shut off right away and decided to replace passenger side with second bulb in twin pack so they would match brightness.

Had to really twist arm and yank and pull wires past air intake on the airfilter to get to passenger side light. By the time I I got the passenger light back in... the driver side no longer worked.

Same initial diagnostics... no power to driver side plug for bulb. I am guessing I yanked on something on the passenger side that caused the driver side to be messed up.

Would love to hear a simple solution as I am electrically challenged to fix this myself.

It is now end of September 2010... what solution did you find????

Thanks for any input.

Kyle

 

I sold it and bought a Silverado... no more light issue!


I can tell you for sure that it wasn't the CTM, light switch, dimmer switch, connections, or anything else that we could find. Some people said it may be the BCM (Body Control Mod?) others said its most likely a pinched / cut wire somewhere... but to find it they would have to rip everything apart at 75.00 an hour.

its going to cost a TON to troubleshoot and fix

 

Kept looking for where I might have yanked on something.

Crawled under steering wheel to locate the ICM... pushed on some wires, looked around... when back to checking at headlight and metered voltage suddently.

Put bulb back in and by time I hooked it up the voltage was gone.

Played around with tilt steering as noted in this thread... pushed on ICM... got voltage back.

Got bulb back in and mounted... headlight is still working two days later.

Note to self... set tilt steering to one setting and DON'T TOUCH.

 

Update...

I eventually found the bundle of wires causing the problem although have not found specific culprit.

Basically found bundle that travels just above the emergency break to the side panel next to my left foot. I can grab that bundle wher it follows a support bar (about 3/4-1" t structural tubing) right above my left shin.

I can push on the bundle forward and the left head light goes out. Pull back and up and the headlight comes on. Very consistent. Took a zip tie and pulled bundle into the up and back position. Still need to get under and into things to see where and what is hitting and what is shorting out.

More later but at least I feel good narrowing down the situation and not feeling like I need to dump the car (yet).

 

I had a similar issue with my dodge 1500. I had no power to my right headlight on low or high beam. I also noticed when driving in a light rain that my windshield washer button was not activating the pump.

I checked under the dash and the sea of wires looked hopeless. If there was a fray in there, it was staying.

There were other posts that mentioned bad grounds, so I checked under the hood near the right headlight. The wires to the headlight and to the windshield washer pump were wrapped in the same bundle and connect to the right side of the engine compartment. About two feet from the front of the truck on the right sidewall, there is a ground wire that comes out of that bundle and connects to a screw. I tightened the screw, and the right headlight and washer pump both work fine. On my truck, that screw is being used to hold down an after-market cold air intake shield. I guess when the shield was put on the screw was tightened and slowly became loose. Even if you don't have the cold air intake, be sure that screw it tight. There are grounds all over the side walls in the engine compartment. Check on the left sidewall for a similar ground for the left headlight.

Make sure to take the screw completely out so you can use a wire brush to clean the sidewall and grounding wire contact. Then reinstall and tighten.

Good luck,
Max