How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Chris Your Own Question
Chris
Chris, Shop Foreman
Category: Dodge
Satisfied Customers: 13128
Experience:  Dodge/Cummins and Chrysler Certified Master Tech
12365498
Type Your Dodge Question Here...
Chris is online now
A new question is answered every 9 seconds

My low beam won't work. Changed bulbs, fuses and dimmer

Customer Question

My low beam won't work. Changed bulbs, fuses and dimmer switch. I'm trying to find where the forward control module is located
JA: Most vehicles have two fuse panels. Have you located both?
Customer: yes, checked all fuses
JA: What is the model/year of your Dodge?
Customer: 2001 Dodge Ram 5.2 Liter
JA: Are you fixing your Ram yourself? What have you tried so far?
Customer: Where is the computer module located?
JA: Anything else you want the mechanic to know before I connect you?
Customer: no
Submitted: 2 months ago.
Category: Dodge
Expert:  Dan replied 2 months ago.

Does it have DRL lights? Does it have quad headlights?

Customer: replied 2 months ago.
It has fog lights. Everything I'm reading is pointing to the FCM. Where is that located? I found a module up against the wall in front of passenger side with 3 plugs going into it. Looks like 4 screws to remove it. Is that it?
Expert:  Dan replied 2 months ago.

Do you have a wiring diagram for the low beams?

Customer: replied 2 months ago.
Where is the forward control module on my 2001 Dodge Truck?
Customer: replied 2 months ago.
This will now make the 4th time I've asked this page in a row, where is the forward control module located in my truck?
Expert:  Chris replied 2 months ago.

Hello, my name is ***** ***** I am sorry that you are not getting an answer. Your truck has a CTM (Central Timer Module ) instead of a FCM. The CTM is mounted under the dash to the right of the steering column. It is a black medium sized module. Let me know if you find it.

Chris

Customer: replied 2 months ago.
Thank you. I'll check for it now
Customer: replied 2 months ago.
I believe I found it. Thank you. Am I correct, when saying that module runs the the headlights through it?
Expert:  Chris replied 2 months ago.

The module controls interior lighting, and can flash the headlamps for the factory security system, but does not directly control the low beams. That did not happen until 2002.

Chris

Expert:  Chris replied 2 months ago.

Click on the link below to see the headlight diagram. The switch actually grounds the circuit. After it passes through the high beam switch.

Chris

Customer: replied 2 months ago.
I don't understand what you mean by " the switch grounds the circuit, etc..
Expert:  Chris replied 2 months ago.

Positive battery voltage goes to each bulb. Then the ground side goes back through the high beam switch, then to the headlight switch. When the switch is turned on, it completes the circuit by grounding it. Look at the wiring diagram. Then you will understand.

Chris

Customer: replied 2 months ago.
Thank you sir. I'll study it more closely when I return home. Basically, I need to figure out what to replace to get my low beam working again. I don't necessarily want to know how everything works, just what I need to do to fix it.
Expert:  Chris replied 2 months ago.

Gotcha. Well if you start by using a 12 volt test light and check for voltage at the headlight bulb connector and have voltage, then follow the diagram back through the high beam switch and then to the headlight switch. You should be able to find the problem. Check that connector at the high beam multifunction switch. I have seen issues there in the past.

I hope that this information is helpful and please don't forget to rate my service using the just answer star rating system. I would really appreciate it. I will still be able to help you out even after you rate me.

Thank you!

Chris

Customer: replied 2 months ago.
Thank you. We've checked from bulb to fuse boxes. Couple parts guys were saying it was the computer module that's messed up sending bad signal. On low beam, all 3 connections are hot, then on high beam, 2 hot and 1 ground. Something in "low" is causing the ground to not work. That was why they were leaning towards a malfunction in computer. It wouldn't be the ECM would it? That's the only other module. (And a lot easier to change too!)
Expert:  Chris replied 2 months ago.

No, the ECM is for engine systems only. I bet that the problem is up at the multifunction high beam switch on the steering column.

Chris

Customer: replied 2 months ago.
I put in a whole new dimmer switch in the steering column too. Is that the part you mean?
Expert:  Chris replied 2 months ago.

Yes. Are the wires and terminals in that connector ok?

Customer: replied 2 months ago.
I don't know if my buddy tested the wires and connections when he swapped it out or not. I don't remember seeing him do that. He said everything looked fine... I will say the wipers, blinkers and high/low switch are working just fine though.
Expert:  Chris replied 2 months ago.

Ok, let me check a few things and get back to you

Expert:  Chris replied 2 months ago.

Ok, what I want you or your mechanic to do is to gain access to that connector that plugs into the multifunction switch and get a jumper wire. Ground one end of the jumper wire, and then touch the other end to the multifunction connector terminal # 18. It is a Violet wire with a White stripe. That should make the right side low beam come on. Try that and let me know if it comes on.

Chris

Customer: replied 2 months ago.
Can you please be more descriptive about which connector you mean? Sorry, all this is brand new for me.
Expert:  Chris replied 2 months ago.

No problem. The connector that plugs into the dimmer switch (also known as the multifunction switch) There should be a Violet wire with a White stripe on it. If you ground that wire's terminal, the right low beam should turn on. Hope that helps,

Chris

Customer: replied 2 months ago.
Ok, that makes sense. Thank you
Expert:  Chris replied 2 months ago.

You are welcome. Let me know how it goes!

Chris