K 2500 Truck 4WD V8-379 6.2L DSL VIN C FI (1989)
Torque Converter Clutch Solenoid: Technical Service Bulletins
A/T - TCC Wiring Shorted to Ground, Blown Fuses
GMC NUMBER:
89-7A-108
GROUP:
7A-Automatic Transmission
DATE:
October,1989
CORPORATE
NUMBER:
977140
SUBJECT:
POSSIBLE BLOWN VEHICLE FUSES ON CIRCUITS 420,422, OR 446 DUE TO SHORTED TCC WIRING
MODELS:
1989 C1, C2, K1, K2, R1, V1, S1, T1 TRUCKS M AND G VANS WITH 700R4/HYDRAMATIC 4L60
BULLETIN COVERS:
Service and parts information for transmission Torque Converter Clutch (TCC) solenoid wiring which may exhibit a breakdown in insulation. This loss
of insulation and possible short to ground may cause conditions affecting the vehicle's transmission, electrical system and engine performance. For
example, the short may cause blown fuses and/or conditions such as loss of air conditioning, ECM, instrument cluster, etc. Due to electrical design
differences, each vehicle line may display unique conditions. A short in the TCC circuit will usually blow a fuse on the circuit containing the TCC
solenoid. To help determine which fuse may affect an individual model, refer to the "Diagnosis Information" section of this bulletin.
IMPORTANT:
Diagnosis information in this bulletin is not contained in any Service Manual.
Figure 1
DATE OF PRODUCTION CHANGE: (Figure 1)
Changes to the TCC solenoid wiring entered production effective May 17,1989 (Julian Date 137) on all 1989 700- R4/HYDRA_MATIC 4L60 and THM
200-4R transmissions.
