P1790

DTC P1790: Problem in Throttle Position Sensor Circuit

NOTE: Record all freeze data and review General Troubleshooting Information before you troubleshoot.

1. Turn the ignition switch ON (II).
2. Check whether the OBD II scan tool indicates code for the throttle position (TP) sensor.
Does the OBD II scan tool indicate code for TP sensor?
YES-Do the DTC Troubleshooting for the TP sensor circuit low voltage, and the TP sensor circuit high voltage. Recheck for DTC P1790 after troubleshooting.
NO-Turn the ignition switch OFF, then go to step 10.
3. Disconnect TCM connectors A (26P) and B (22P).
4. Turn the ignition switch ON (II).





5. Measure the voltage between TCM connector terminals B20 and A4 or A17.
Is there 4.75 - 5.25 V ?
YES-Go to step 6.
NO-Repair open or short in VREF wire between TCM connector terminals B20 and the ECM.
6. Close the throttle fully.





7. Measure the voltage between TCM connector terminals B4 and A4 or A17.
Is there 0.44 - 0.56 V?
YES-Check for loose terminal fit in the TCM connectors. If necessary, substitute a known-good TCM and recheck..
NO-Repair open or short in the wire between TCM connector terminal B4 and the TP sensor.