U1020
Diagnostic Trouble Code (DTC) ChartsP0102 - P0181 Powertrain Codes (DTC):
P0102-P0181
P0182 - P0350 Powertrain Codes (DTC):
P0182-P0350
P0351 - P0460 Powertrain Codes (DTC):
P0351-P0460
P0500 - P0761 Powertrain Codes (DTC):
P0500-P0761
P0765 - P1152(Natural Gas Vehicle) Powertrain Codes (DTC):
P0765-P1152 (NATURAL GAS MODELS)
P1152(All Other Models) - P1451 Powertrain Codes (DTC):
P1152 (ALL OTHERS) - P1451
P1460 - P1701 Powertrain Codes (DTC):
P1460-P1701
P1702 - P1788 Powertrain Codes (DTC):
P1702-P1786
P1787 - Uxxxx Powertrain Codes (DTC):
P1787-UXXXX
NOTE 1: DTC P1000 is ignored in Key ON Engine OFF (KOEO) AND Key ON Engine Running (KOER) Self-Test. Disregard the DTC P1000 and continue as directed.
NOTE 3: Go to Transmission and Drivetrain to perform complete diagnosis. Testing and Inspection
NOTE 4: Go to Heating and Air Conditioning to diagnose: U1020 SCP invalid or missing data for A/C clutch. Testing and Inspection
NOTE 5: Go to Anti-Lock Brake System (ABS) to diagnose: U1039 SCP invalid or missing vehicle speed message or U1051 SCP invalid or missing data for brakes. Testing and Inspection
NOTE 6: Go to Lighting and Horns to diagnose: U1135 SCP invalid or missing data from ignition switch/starter steering column ignition lighting (SCIL) control module. Lighting and Horns
NOTE 7: Go to the Antitheft and Alarm System to diagnose: U1451 SCP invalid or missing data from anti-theft module. Testing and Inspection
NOTE 8: Go to the Fuel Delivery and Air Induction to diagnose: U1850 SCP invalid or missing data for fuel system. Fuel Delivery and Air Induction
NOTE 9: For "U" DTCs received during the self-test of another module; GO to Symptom Charts, Symptom Chart 31. Testing and Inspection