Failure Conditions

When the valve relay is engaged, the valve relay feedback line (EBCM pin 32) should be at battery voltage. With the valve relay disengaged, the feedback line should be at ground. If the commanded position of the valve relay and the valve relay position indicated by the feedback line do not agree, ABS Code 12 will set. See Fig 2 .

Fig 1: ABS Code 12: Valve Relay Error Circuit Diagram

Courtesy of GENERAL MOTORS CORP.

Fig 2: ABS Code 12: Valve Relay Error Diagnostic Flow Chart

Courtesy of GENERAL MOTORS CORP.