K 2500 3/4 Ton Pickup 4WD V8-350 5.7L VIN L 4-bbl (1983)
Fig. 14
Rear Wheel Anti-Lock (RWAL) Brake System Code 7 diagnosis. Shorted isolation valve or faulty ECU
GMC Workshop Service and Repair Manuals
Diagnostic Trouble Code Descriptions|Page 4537 >
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