Adjustment of shifting performance,automatic transmission
Symptom: Diagnostic trouble codes P1786, P1787 or P1788 generated in the TCM system.Hard shifting when the TCS is activated.
Adjustment of shifting performance, automatic transmission |
Fault symptom
Diagnostic trouble codes P1786, P1787 or P1788 generated in the TCM system.Hard shifting when the TCS is activated.
Diagnostic procedure
2. |
Use the ISAT to communicate with the TCM system and select
"TCS ACTIVE" in the "READ ON/OFF" menu.
Activate the TCS by engaging a gear and driving the front wheels while the front assembly of the car is raised. Check whether the ISAT display text changes from TCS OFF to TCS ON at the same time as the TCS lamp lights up. If it does not, check the cable between pin 12 of the TCS control module and pin 4 of the TCM control module for continuity/shorting. |
3. |
Use the ISAT to communicate with the TCM system and select
"TCS THROTTLE POSITION" in the "READ FUNCTIONS" menu.
Check that the throttle position is about 70-92%% when the wheels are stationary and that it changes to a much lower figure when the speed of the front wheels exceeds 4 km/h. If it does not, check the cable between pin 4 of the TCS control module and pin 15 of the TCM control module for continuity/shorting. |