P0137 Code

[james182]

My 2007 6.7 2500 just threw a P0137 code. I know this means "o2 Sensor 1/2 Circuit Low" but now what? Can somebody please shed some light on this for me. Where should I look? Does this just mean there are some parts that need replacing, or do I need to do a little digging first?

 

[Bob4x4]

The engine aftertreatment system monitors the Oxygen Sensor (O2) content in the diesel engine exhaust. The Engine Control Module (ECM) monitors the exhaust gases for oxygen content and varies the rich/lean fuel mixture of the intake air fuel mixture to adjust the system. This diagnostic monitors the status message broadcast by the Smart O2 Sensor Module for the downstream O2 Sensor circuit. The ECM will set the fault if it receives a Failure Mode Indicator (FMI) message from the Smart O2 Module. The ECM will illuminate the MIL lamp immediately when the diagnostic runs and fails. The ECM will turn off the MIL lamp diagnostic runs and passes in four consecutive drive cycles.

 

[Bob4x4]

Possible Causes

(K299) O2 1/2 HEATER SUPPLY CIRCUIT OPEN
(K80) O2 1/2 HEATER RETURN CIRCUIT OPEN
(K734) O2 1/2 PUMP CURRENT CIRCUIT OPEN
(K904) O2 1/2 RETURN CIRCUIT OPEN
(K733) O2 1/2 PUMP CELL CURRENT TRIM CIRCUIT OPEN
(K141) O2 1/2 SIGNAL CIRCUIT OPEN
O2 SENSOR MODULE

 

[Bob4x4]

Might also want to see if your truck has any recalls oustanding(G30) and any software updates

 

[james182]

So besides checking for flash updates, where do I start diagnosing? How do I confirm which circuit is open?

 

[xcc_rider]

You have declined PM's in your profile. If you enable it I can send you a pm that will help you out.

 

[james182]

PM setting updated.

 

[xcc_rider]

For some reason this site is fubar on my tablet right now and I can't get any of the tabs to either show or work so I can't pm you the link.
Email me at xcc_rider(at)Yahoo(dot)com and I'll include the link in the reply.