AT-PZEV Models
DTC P1851: Problem in Creep Aid System Solenoid Valve B Circuit2003 AT-PZEV (SULEV) and 2004-2005 AT-PZEV Models
NOTE:
^ Record all freeze data and review General Troubleshooting Information before you troubleshoot.
^ This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
1. Clear the DTC with the HDS.
2. Check that DTC P1851 recurs.
Is DTC P1S51 indicated?
YES- Go to step 6.
NO- Go to step 3.
3. Warm up the engine to normal operating temperature (the radiator fan comes on).
4. To do an auto idle stop, drive the vehicle in the D position for several minutes at speeds over 10 mph (15 km/h). Apply brakes to slow down and stop the wheels (the vehicle comes to a stop in auto idle stop, and the auto stop indicator in the gauge assembly will blink), and keep pressing the brake pedal.
5. Release the brake pedal, and check that DTC P1851 recurs.
Is DTC P1S51 indicated?
YES- Go to step 6.
NO- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the creep aid system solenoid valves and TCM.
6. Turn the ignition switch OFF.
7. Disconnect TCM connectors A (31P) and B (24P).
8. Turn the ignition switch ON (II).
9. Measure the voltage between TCM connector terminals B5 and A23 or A24.
Is there voltage?
YES- Repair short to power in the wire between TCM connector terminal B5 and the creep aid system solenoid valve B.
NO- Go to step 10.
10. Turn the ignition switch OFF.
11. Disconnect the 4P connector from the creep aid system solenoid valves A and B.
12. Check for continuity between TCM connector terminals B5 and A23 or A24.
Is there continuity?
YES- Repair short to ground in the wire between TCM connector terminal B5 and the creep aid system solenoid valve B.
NO- Go to step 13.
13. Connect creep aid system solenoid valves A and B connector.
14. Measure the resistance between TCM connector terminals B5 and A23 or A24.
Is there 8 - 24 Ohms?
YES- Check for loose or poor connections at TCM connector terminals B5. If the connections are OK, update the TCM if it does not have the latest software, or substitute a known-good TCM, then recheck. If the symptom/indication goes away with a known-good TCM, replace the original TCM.
NO- Check for an open in the wire between TCM connector terminal B5 and the creep aid system solenoid valve B. and between the creep aid system solenoid valve B and ground (G201). If the wire is OK, replace the creep aid system solenoid valves A and B. then go to step 15.
15. Clear the DTC with the HDS
16. Warm up the engine to normal operating temperature (the radiator fan comes on).
17. To do an auto idle stop, drive the vehicle in the D position for several minutes at speeds over 10 mph (15 km/h). Apply brakes to slow down and stop the wheels (the vehicle comes to a stop in auto idle stop, and the auto stop indicator in the gauge assembly will blink), and keep pressing the brake pedal.
18. Release the brake pedal, and check that DTC P1851 recurs.
Is DTC P1S51 indicated?
YES- Return to step 6 and recheck.
NO- The problem has been corrected.