Stranded wth signal/headlight problem

[mwurts]

I am a new subscriber hoping some one can help.

The truck is a stock '03 3500 series used for hauling RVs and I'm stranded in

Vancouver,BC.

All lights were working on shutdown, but on the next startup 24 hours later

one headlight is working on lowbeam only and the other on highbeam only.

I relplaced a headlite bulb and the problem did not change.

At this point I realized that 3 out of the 4 signals were also not working.

Park and tail lights are OK.

A dealer shop replaced what they called a "front control module" with no success and I'm still stranded. ... help.

 

[RJOL]

I am a new subscriber hoping some one can help.

The truck is a stock '03 3500 series used for hauling RVs and I'm stranded in

Vancouver,BC.

All lights were working on shutdown, but on the next startup 24 hours later

one headlight is working on lowbeam only and the other on highbeam only.

I relplaced a headlite bulb and the problem did not change.

At this point I realized that 3 out of the 4 signals were also not working.

Park and tail lights are OK.

A dealer shop replaced what they called a "front control module" with no success and I'm still stranded. ... help.

If you have a dealer looking at it, I don't know if I can add anything that they wouldn't already have checked.



The 3rd Gens lights are basically controlled by computer. Here is a copy of the manual that talks about this area:



3. 10 INSTRUMENT CLUSTER

The DR Instrument Cluster is a new type of

control module that includes the hardware and

software necessary to function as the cluster and

the body control module. The Instrument Cluster

houses the Speedometer, Tachometer, Fuel gauge,

Coolant Temperature gauge, Oil Pressure gauge,

and the Voltage gauge. The cluster positions all of

the gauges using PCI bus messages received from

the PCM. The cluster contains certain warning

indicators, depending on engine type and options.

Some of the indicators are hardwire inputs and

some indicators are controlled via PCI bus messages.

The warning chime tone generator is contained

within the cluster. The cluster includes a

vacuum fluorescent (VF) display for the PRNDL,

Total and Trip Odometers. The VF will also display

warning messages such as door ajar, low washer

fluid level, engine hours, and no bus communications.

The cluster has the ability to set and store

DTCs, communicate on the PCI bus, display engine

information, and display certain inputs using the

DRBIIIt.

The following systems are controlled either completely

by the Instrument Cluster or in conjunction

with other inputs received by hardwire or via the

PCI bus:

² Audible Warnings

² Brake Lamp Control

² Brake Transmission Shift Interlock (BTSI)

² Cargo Lamp Control

² Central Locking

² Door Lock Inhibit

² Enhanced Accident Response

² Exterior Lighting Control

² Exterior Lighting Fail-Safe

² Heated Seat Control

² Horn Control

² Interior Lamp Control

² Interior Lamps - Enhanced Accident Response

² Interior Lamps Load Shedding

² Lamp Out Indicator Control

² Panel Lamps Dimming Control

² Parade Mode

² Power Locks

² Remote Keyless Entry (RKE)

² Remote Radio Switch Interface

² Rolling Door Locks

² Turn Signal and Hazard Warning Lamp Control

² Vacuum Fluorescent Display Synchronization

² Vehicle Theft Security System (VTSS)

CAUTION: Instrument clusters used in this

model automatically configure themselves

for compatibility with the features and

optional equipment in the vehicle in which

they are initially installed. The instrument

cluster is programmed to do this by

embedding the Vehicle Identification Number

(VIN) and other information critical to proper

cluster operation in electronic memory. This

embedded information is learned through

electronic messages received from other

electronic modules in the vehicle over the

Programmable Communications Interface

(PCI) data bus, and through certain hard

wired inputs received when the cluster is

connected to the vehicle electrically.

Once configured, the instrument cluster

memory may be irreparably damaged and

certain irreversible configuration errors may

occur if the cluster is connected electrically to

another vehicle; or, if an electronic module

from another vehicle is connected that

provides data to the instrument cluster

(including odometer values) that conflicts with

that which was previously learned and stored.

Therefore, the practice of exchanging

(swapping) instrument clusters and other

electronic modules in this vehicle with those

removed from another vehicle must always

be avoided. Failure to observe this caution

may result in instrument cluster damage,

which is not reimbursable under the terms of*

the product warranty. Service replacement

instrument clusters are provided with the

correct VIN, and the certified odometer and

engine hours values embedded in cluster

memory, but will otherwise be automatically

configured for compatibility with the features

and optional equipment in the vehicle in

which they are initially installed.



There is more, but the main thing is that it's a lot more complicated then a switch or fuse...

 

[mwurts]

Thank-you, Rick, for the reply and info. It definately sounds a bit more complicated than a fuse. The vehicle has had no module swaps from other vehicles so it would seem from your info that the PCM is the 'possible' culprit. Could you possibly provide some info on exactly where the PCM is located. Under the hood on the firewall on the passenger side?? The dealer shop is still looking so I hope tomorrow is more successful than today.

 

[sag2]

If it was wet it could be a connector full of water. The FCM the dealer replaced controls many of the lighting functions. The light inputs and outputs can be seen on the DRBIII, so the dealer should be able to diagnose it.

 

[mwurts]

stranded now fixed

the dealer shop replaced the entire fuse control box, as well as the front control module, and the problem was solved.



thank you all for your input.



milt