Code B335, Loss Of ECCP Serial Data

This code can only be viewed as a "history" code because if it was current, service diagnostics could not be entered. Most likely the ECCP controls for heating and A/C will also be inoperative when the loss of serial data occurs.

Since the serial data lines are redundant, a double open in the circuit No. 800 has to occur to set this code; however, the code will also set for a single open in the power or ground supply to the ECCP.

NOTE: Loss of ECCP ground will cause data line circuit No. 800 to be tied to system voltage, disabling all vehicle self-diagnostics.

Fig 1: Code B335, Schematic, Loss of ECCP Serial Data

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code B335, Harness View, Loss of ECCP Serial Data

Courtesy of GENERAL MOTORS CORP.