C0121

C0121-VALVE RELAY CIRCUIT MALFUNCTION





DTC C0121





VALVE RELAY CIRCUIT MALFUNCTION

The Electronic Brake And Traction Control Module (EBTCM) uses a relay to control valve solenoids. When ignition is in Run, the module energizes the relay to apply voltage to the solenoids. The module will disable the relay when ignition is in the OFF position or fault is detected.

DTC PARAMETERS
DTC C0121 will set if:
^ If the EBTCM commands the relay On, but does not sense battery voltage at the solenoids.
^ If the control module commands the relay Off, but senses battery voltage at the solenoids.

When DTC CO 121 sets:
^ The ABS telltale will be On.
^ The EBTCM will disable ABS and TCS.

DIAGNOSTIC AIDS
An open in circuit 140 or in circuit 702 will set this DTC. Inspect these circuits for a wiring fault.
This relay is inside the EBTCM and is not serviceable. The EBTCM should be replaced if no wiring fault is located.