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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information

Condition




The transmission control module (TCM) receives a signal about input and output speed from the transmission rpm and speed sensor. There is a specific ratio for each gear, and using the signals the control module calculates the transmission gear ratio. Diagnostic trouble code (DTC) TCM-0028, TCM-0029, TCM-002A, TCM-002B or TCM-002C (depending on fault cause) is stored if the transmission control module (TCM) registers that the gear ratio deviates by more than 10%.
The diagnostic trouble code (DTC) can be diagnosed at an oil temperature of above +20 °C in the transmission and for:
- TCM-0028 Gear 1 and engine speed (RPM) above 500 but below 1260 rpm, as well as throttle opening greater than 50% and gear ratio = 2.301 +/- 4%
- TCM-0029 Gear 2 and engine speed (RPM) above 500 rpm, as well as throttle opening greater than 10% and gear ratio deviation greater than 20%
- TCM-002A Gear 3 and engine speed (RPM) above 500 rpm, as well as throttle opening greater than 10% and gear ratio deviation greater than 20%
- TCM-002B Gear 4 and engine speed (RPM) above 500 rpm, as well as throttle opening greater than 10% and gear ratio deviation greater than 20%
- TCM-002C Gear 5 and engine speed (RPM) above 500 rpm, as well as throttle opening greater than 10% and gear ratio deviation greater than 20%.

Substitute value
- Emergency program Emergency mode 1 in the transmission control module (TCM) has been initiated.

Hint: Emergency mode in the event of a fault Emergency Mode In the Event of A Fault

Possible source
- Contact resistance in the circuit for the solenoids. See the table below:





- One of the shift solenoids has jammed in the OFF or ON position. See the table below:





- Mechanical fault in the transmission. Worn components in the transmission causing slippage or too low line pressure.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit
- General warning lamp lit
- Abnormal slipping gear shifting
- Harsh gear shifting
- No shifting.