K 2500 Truck 4WD V8-379 6.2L DSL VIN C FI (1989)
Radio/Stereo: All Technical Service Bulletins
Audio - Diagnosis with the Tech1 Scan Tool
GMC NUMBER:
92-9A-65
GROUP:
9A Audio Systems
DATE:
March, 1992
CORPORATE
NUMBER:
268101
SUBJECT:
RADIO DIAGNOSIS (INSTALLATION OF JUMPER WIRE FOR CAMS AND TECH 1 DIAGNOSIS)
MODELS:
1988-1992 C/K
Radio conditions may be more accurately diagnosed on C/K and TopKick/Kodiak vehicles by using a Tech I or CAMS T-100. Radio system diagnosis
with the Tech I requires body cartridge TK03040B and the T-100 requires the use of ALDL E&C (Entertainment and Comfort) adapter, part number
56746.
On the aforementioned vehicles, the radio system consists of a radio control head, radio receiver, cassette deck, and graphic equalizer. The Tech I or
T-100 when used can override and simulate the radio control head. The Tech I or T-100 allows you to monitor or transmit messages to and from any
radio system component.
This makes testing of the receiver, balance controls, volume, fader, individual speakers, clock, station select, and other features possible. The technician
can then accurately attribute a given condition to a specific component rather than remove each of the separate units for diagnosis and repair.
Cassette tape player functions cannot be tested with this system; however, a more accurate diagnosis can still be made by verifying correct operation of
the other system components.
Please refer to the Tech I or T-100 handbook for more detailed entertainment system diagnosis information.
To apply Tech I or CAMS T-100 diagnostics to C/K or TopKick/Kodiak vehicles, a jumper wire between ALDL connector terminal "J" and the radio
receiver must first be installed (Figure 1).
SERVICE PROCEDURE:
