Standardized Test Procedure

Trucks years affected: 1998-1999

Symptom: interfering signal on five 1998 pickup trucks sounds like a clean carrier and may drift in frequency. The problem did not appear to be wide band noise.  

This problem is caused by a defective truck air bag computer module. I spoke with Mr. Bill Gilmore, Chrysler's RFI Truck Product Engineer team leader. Bill is a licensed radio amateur and is well informed on the issues involved. He indicated that Chrysler has a new design for this defective air bag computer module, effective with the model year 2000. The drifting nature of the interference is probably due in part to the use of a ceramic resonator instead of a quartz crystal in the embedded controller.  

Solution: Contact a Chrysler dealership, and ask them to install a model year year 2000 air bag computer module to replace the defective one. The specific service bulletin on the Dodge Ram pickup air bag computer module is numbered 08-32-99. This should direct the dealership to the exact location. 

Any questions about the air bag module exchange can be directed to:
William N. Gilmore Jr.
Product Engineer Truck
Platform Engineering
Chrysler Corp.
14250 Plymouth Road
Detroit, MI 48227-3086
(313) 493-3473

Notes: Connecticut DOT has experienced RFI from fuel pumps in this same pickup.  They also advised there is also a fuel pump tech note out. You may want to look into that problem. ConnDOT had the fuel pump issue resolved by the dealership. I have not seen this trouble.

Follow up:  NOTES on Dodge 2001 Ram 2500 V8 pickup w/gas engine

Some wide band noise was noticed on this pickup. Antenna placement had a definite effect on noise level:

on driver's side fender=1.3 uVolts
on roof = .8 uV
on rear bed (roll bar) =.5 UV

Placing the antenna toward the rear of the 2001 model year vehicle brought this vehicle into noise level compliance.