Diagnostic Trouble Code (DTC) Information TCM-0042

Condition 

Fig 1: Identifying Oil Temperature Sensor

Courtesy of VOLVO CARS CORPORATION

The oil temperature sensor transmits a signal to the transmission control module (TCM) which is used for various functions, such as temperature controlled lock-up and the initiation of high-temperature programs. The sensor has an NTC (negative temperature coefficient) resistor. The signal (voltage) decreases with increasing oil temperature. The diagnostic trouble code (DTC) is stored if the transmission has been subjected to high loads over an extended period. The time that is required to store the diagnostic trouble code (DTC) is greatly temperature-dependent, and only oil temperatures above 100 °C will affect this diagnostic trouble code (DTC).

The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value 

• The transmission control module (TCM) assumes an oil temperature of 80 °C.

Possible Source 

• Short-circuit to ground in the signal cable
• The oil temperature sensor does not work
• The transmission has been exposed to extreme load and high ambient temperature.

Fault symptom[s] 

• General warning lamp lit.