P1790

Circuit Description
Transmission Side Read Only Memory (ROM) and Electronically Erasable Programmable Read Only Memory (EEPROM) is an electronic circuit that controls the transmission controls in the Powertrain Control Module (PCM).
This DTC detects a check sum error. This is a type "B" DTC.

Conditions For Setting The DTC
- Detects check sum error for 1 second.

Action Taken When The DTC Sets
- Maximum line pressure.
- Immediate landing to 4th gear
- Inhibit TCC engagement.
- The PCM will illuminate the Malfunction Indicate Lamp (MIL) and CHECK TRANS Lamp.

Conditions For Clearing The MIL/DTC
- The PCM will turn oft the MIL and CHECK TRANS Lamp after three consecutive ignition cycles without a failure reported.
- The DTC can be cleared from the PCM history by using a scan tool.
- The DTC will be cleared from history when the vehicle has achieved 40 warmup cycles without a failure reported.
- The PCM will cancel the DTC default actions when the fault no longer exists and the ignition is cycled "off' long enough to power down the PCM.





DTC P1790 ROM Transmission Side Bad Check Sum