P1790

P1790-FAULT IMMEDIATELY AFTER SHIFT
- When Monitored:
After a Gear Ratio Error code is stored.
- Set Condition:
After a Gear Ratio Error DTC has already been set. The DTC is set if the fault happened within 1.3 seconds of a shift. The DTC set time will vary from 1.214 seconds to 15 seconds.

Possible Causes
- FAULT AFTER SHIFT

Always perform the 42RLE Pre-Diagnostic Troubleshooting Procedure before proceeding. 42RLE Automatic Transmission

Theory of Operation
This DTC is not stored alone. It is stored if a Gear Ratio DTC is detected immediately after shift. The existence of DTC P1790 indicates a mechanical or hydraulic (not electrical) related problems. It should be noted, however, that all mechanical problems don't necessarily result in DTC P1790. When this DTC exists, diagnosing the system should be based on the associated DTC and only mechanical causes should be considered.

Diagnostic Test
1. FAULT AFTER SHIFT
This DTC is set along with a Gear Ratio DTC. Perform the appropriate test for the Gear Ratio DTC stored.

NOTE: Check Pending DTC's or 1 trip failures if there are no Active or Stored Gear Ratio DTC's.

View repair.
Repair
Refer to the Transmission category and perform the appropriate diagnostic procedure.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. Verification Tests