Owners of some Jeep models may experience a MIL illumination or the ECT light illuminated at temperatures below 32-degrees F. Further investigation may find that DTC P0123 (throttle position sensor 1 circuit high) or P0222 (throttle position sensor 2 circuit low) are active and stored.
This TSB applies to 2007-2009 Cherokee, 2007-2009 Liberty, and 2007-2009 Nitro models, equipped with the 3.7L engine, built before February 20, 2009.
Using a scan tool (StarSCAN) with the appropriate diagnostic procedures available in TechCONNECT, verify that all engine systems are functioning as designed. If DTCs other than those listed here are present, record and repair as needed before proceeding with this TSB.
If the above condition is present when temperatures were below 32-degrees F and no other DTCs exist, perform the repair procedure. If the temperatures were above freezing, then follow the diagnostic procedures available in DealerCONNECT/TechCONNECT.
NOTE: Perform the ETC relearn procedure after replacing the throttle body. Be sure to erase any DTCs that may be set.
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