FixVault

Possible Causes

Possible Causes 
(K902) O2 UPSTREAM RETURN CIRCUIT SHORTED TO GROUND
(K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND
(K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO (K902) O2 UPSTREAM RETURN CIRCUIT
(K43) O2 2/1 SIGNAL SHORTED TO THE (Z904) HEATER GROUND CIRCUIT
O2 SENSOR
PCM

Always perform the  PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE  before proceeding.