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2016 Traverse 3.6L Readiness Monitors Not Completing
Hi, I have a 2016 Traverse in my shop with a 3.6 liter engine. It has been driven hundreds of miles and many drive cycles. It will not set the following readiness monitors: 02heater, 02 sensor, catalyst, and fuel system. There is no check engine light but it is setting codes U0121 and U0140, usually when the key is on before starting the vehicle. Communication with these modules with the scan tool is fine. No other ecm codes. Are the communication codes something to go after? I am not seeing anywhere in the service info that this should be a problem. The car does run 11 to 15% rich on bank 1 with some misfiring detected on bank 1 at high rpm, no load. Again, is this a reason for not setting the monitors? The misfire codes and monitors have all run and passed. It appears like none (approx 18) of the 02 sensor codes have even run but the criteria for running them as written in the service manual is all there. Any input?
Ok thanks. No, I have not been able to verify the ECM programming number at this point. In a recent discovery I found that the ECM is staying awake and online after the BCM and ABS go offline on a vehicle shut-down key off. I believe this is when it's setting the comm codes.
I found with this vehicle that the ecm serial data wake-up signal was shorted to power in the body harness near the rear fuel pump module. After this was corrected the emissions monitors set normally.
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