Cruise Control - Control Response

88chevy18

Number:REISSUE 88-288-9B

Section: 9B

Date: SEPT., 1988
Subject: CRUISE CONTROL RESPONSE


Model and Year: 1988 G20 VANS WITH 6.2L DIESEL ENGINE
AND (K34) CRUISE CONTROL
TO: ALL CHEVROLET DEALERS


Chevrolet Dealer Service Bulletin 88-288-9B dated July, 1988 is being reissued to provide Chevrolet VIN breakpoints. The breakpoints listed in the original bulletin were for GMC units. All copies of 88-288-9B dated July, 1988, should be discarded.

Some 1988 G Vans equipped with 6.2L light duty diesel engines (LH6) and cruise control may exhibit a condition involving cruise control response. Accelerating and/or decelerating several mph more than anticipated may occur when the driver uses the Set, Resume, Tap-up, Tap-down, Coast or Accelerate cruise modes. This may be caused by negative voltage transients during glow plug operation.

A cruise control module which is less susceptible to negative voltage transients may be installed.

VEHICLES INVOLVED

1988 Chevrolet G20 vans equipped with 6.2L light duty diesel engines (LH6) and cruise control (K34) built within the following VIN breakpoints:

From Through
J4117090 J4130510

PARTS

Part Name Part Number Quantity
Cruise Control Module 25074713 1

FIGURE 1:

SERVICE PROCEDURE

Cruise control module replace. (Refer Figure 1)


1. Disconnect cruise harness (121).
2. Disconnect module assembly (116) by prying back the retaining clip on the bracket and sliding the module out.
3. Install new module part #25074713.
4. Connect cruise harness.

The labor operation to replace the cruise control module is:

Labor Operation: R1220
Labor time: .3 Hrs.