FixVault

Possible Causes

Possible Causes 
(K902) O2 RETURN UPSTREAM CIRCUIT SHORTED TO GROUND
(K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO GROUND
(K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO (K902) O2 RETURN UPSTREAM CIRCUIT
(K41) O2 1/1 SIGNAL SHORTED TO THE (Z904) O2 1/1 HEATER GROUND CIRCUIT
O2 SENSOR
PCM

Always perform the  PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE  before proceeding.