Headlamps, but no running/parking lamps?

[JHardwick]

My radiator blew a gasket last week, so I took it to my mechanic to replace the radiator. When I went back to pick it up, I had dead batteries and needed a jump. Somebody either left my amp on, or accidentally bumped the switch.

Either way, we jumped it and I turned the lights on to head home and "bam", headlights, but no running lights. No fender markers, no cab lights, no tail lights, no nothing. I flipped on the 4-ways and headed home.

I have 14. 4v to the fuse block, the fuse is good, no codes, wth???

EDIT: I switched the park lamp relay with the starter relay to rule that out ... ... ... . switch maybe?

 

[JHardwick]

No suggestions huh?

I got a switch coming from Dodge tomorrow, we'll see.

 

[Vaughn MacKenzie]

JHardwick I have pretty much the same problem on my '98. It started when I went to turn on the headlights and the switch malfunctioned and sparks went flying. No taillights, running lights, markers, no dash lights.



I thought a new switch would fix the problem but no, same problem. All the fuses are fine, no problems with the electrical connector. I have been able to determine all the lamps are good because if I hold the headlight switch in just the right place I can get them to come on.

 

[sag2]

Just unplug the headlamp switch. As soon as the controller sees the input is missing it turns on the lights for safety. That tells you if it is switch or controller.

 

[JHardwick]

Well, it wasn't the switch ... ... ... ... luckily the dealer let me run out to the truck and try it real quick before I bought it, but the mechanic standing there had no suggestions

 

[JHardwick]

After coming home and poking around on here, and sifting through the service manual, I decided to call back down to the dealer and order a FCM. He has one on the shelf for $173, but are closing early for the holiday. I'll head down Friday morning.

 

[Wayne M.]

After coming home and poking around on here, and sifting through the service manual, I decided to call back down to the dealer and order a FCM. He has one on the shelf for $173, but are closing early for the holiday. I'll head down Friday morning.

I think you're on the right track. I have been reading about FCM failures in the magazine- which I'm not happy about and I believe that controls everything.



BTW How many miles do you have now?

 

[JHardwick]

BTW How many miles do you have now?

Just shy of 470,000 miles :-laf

 

[JHardwick]

I think you're on the right track.

grrrrrrrrrrr, I thought I had it licked too. The FCM did not fix the problem :{

 

[MoparDave]

At this point i think I'd take a close look at the radiator replacement and see if a wire was cut or left loose since it happen right after you had it replaced

 

[JHardwick]

At this point i think I'd take a close look at the radiator replacement and see if a wire was cut or left loose since it happen right after you had it replaced

I talked to my mechanic just a little while ago. He said it was pretty much a straight pull, but he'd look at it if I wanted him too. And after removing the PDC today, to replace the FCM, I'd have to agree.



I think I need to bite the bullet and have Dodge stick the DRB-III on it as much as I hate to.

 

[Wayne M.]

I think I need to bite the bullet and have Dodge stick the DRB-III on it as much as I hate to.

Unfortunately this is the only real way, along with the Body Diagnostic book...





"

DIAGNOSIS AND TESTING - FRONT CONTROL

MODULE

The front control module is a printed circuit board

based module with a on-board micro-processor. The

front control module interfaces with other electronic

modules in the vehicle via the Programmable Communications

Interface (PCI) data bus (J1850). In

order to obtain conclusive testing the Programmable

Communications Interface (PCI) data bus network

and all of the electronic modules that provide inputs

to, or receive outputs from the front control module

must be checked. All PCI (J1850) communication

faults must be resolved prior to further diagnosing

any front control module related issues.

The front control module was designed to be diagnosed

with an appropriate diagnostic scan tool, such

as the DRB III
. The most reliable, efficient, and

accurate means to diagnose the front control module

Fig. 5 INTEGRATED POWER MODULE MOUNTING

TABS

1 - INTEGRATED POWER MODULE MOUNTING HOLES

2 - BATTERY TRAY ASSEMBLY

3 - FRONT CONTROL MODULE

DR 8W-97 POWER DISTRIBUTION 8W - 97 - 5

INTEGRATED POWER MODULE (Continued)

requires the use of a DRB III
scan tool and the

proper Body Diagnostic Procedures manual.

Before any testing of the front control module is

attempted, the battery should be fully charged and

all wire harness and ground connections inspected

around the affected areas on the vehicle. "



From 8W-97- 5/6 in the FSM... .....

 

[JHardwick]

Well, the only dealer in the area open Saturday morning scanned it and said it was either the PDC or the instrument cluster. I'm betting PDC and they quoted me $425 for a new one. I called my regular dealer this morning and they want $301, but it's on national back order :{