LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Jeep >> 2009 >> Compass Limited, ED3, AWD, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> DTCS P000A To P0121 (Gas) >> P0037-O2 Sensor 1/2 Heater Circuit Low >> Possible Causes
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Possible Causes

Possible Causes 
(K299) O2 1/2 HEATER CONTROL CIRCUIT SHORTED TO GROUND
(K299) O2 1/2 HEATER CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
(Z924/Z932) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
OXYGEN SENSOR 1/2
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. See  DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure  . 

scientia non olet · About LEMON Manuals