Aftermarket tires/wheels Presence of aftermarket components that interfere with RF reception Outside interference Remote start antenna Intermittent tire pressure monitoring (TPM) sensor internal DTC Tire pressure monitoring (TPM) sensor Tire pressure monitoring (TPM) transponder Wireless Control Module (WCM)15 (KL) Jeep Cherokee NOTE This bulletin applies to vehicles equipped with 32L Engine (Sales Code EHB) SYMPTOM/CONDITION A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination Upon further investigation, the technician may find the following DTCs set in the PCM memory Multiple codes are usually a wiring harness fault Always try to fix P codes before U codes U1504 will happen when the battery was disconnected and usually goes away itself once things are right PO2 SENSOR 1/2 HEATER CIRCUIT HIGH When Monitored and Set Conditions When Monitored This diagnostic runs when the following conditions are met
Jeep Cherokee U1504 Code 12 21
