Diagnostic Trouble Code (DTC) Information

2004 Volvo S80 L6-2.9L Turbo VIN 91 B6294TSECTION Diagnostic Trouble Code (DTC) Information





Diagnostic trouble code (DTC) information

Condition




The transmission speed signal is transmitted by a sensor on the transmission. The transmission control module (TCM) uses the signal to determine the input shaft speed after the torque converter. This signal is used to compare the transmission speed and the vehicle speed. The transmission control module (TCM) uses this comparison to calculate the gear-shift timing. Engine speed (RPM) and vehicle speed data affects the adjustment of the system pressure, lock-up function control and engine torque reduction. The result is smooth gear-shifting. The control module calculates and compares the transmission speed, the engine speed (RPM) and the speed at the transmission. Diagnostic trouble code (DTC) TCM-0024 is stored if the control module registers a faulty signal when vehicle speed is above approximately 25 km/h.

Substitute value
- The transmission control module (TCM) "Emergency mode I" program has been initiated.

Possible source
- Contact resistance in the terminals.
- Open-circuit, short-circuit to ground or short-circuit to supply voltage in the power supply.
- Open-circuit, short-circuit to ground or short-circuit to supply voltage in the signal cable.
- Defective engine speed (RPM) sensor.

Fault symptom[s]
- General orange warning lamp lit.
- Malfunction indicator lamp (MIL) lit.
- No lock-up function.
- Harsh gear shifting.

Hint: Harsh gear shifting can be caused by:
- No reduction of the line pressure when shifting.
- No reduction of the line pressure when moving the gear selector between positions P-R, N-R and N-D.
- No request for torque limiting to the engine control module (ECM) when shifting.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.