Signal Too Low
Signal too low
Checking the temperature sensor
Hint: In some cases, the diagnostic trouble code (DTC) may be caused by a defective oil temperature sensor. Check the function of the oil temperature sensor first.
- Ignition off
- Read off the oil temperature.
Check that the function of the temperature sensor is OK. Test drive the car to increase the temperature of the transmission fluid. Read off the temperature again. Check that the temperature has increased.
Hint: If the temperature is outside its permitted range, fault-trace the temperature sensor.
Is the oil temperature within its permitted range?
Yes - Checking shift solenoid S3
No - Checking transmission fluid temperature sensor
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Checking shift solenoid S3
- Ignition on
- Gear selector in position P
- Activate solenoid S3.
The value must change between OFF and ON.
Does the value change?
Yes - Intermittent fault
No - Checking the resistance
-------------------------------------------------
Checking the resistance
- Ignition off
- Disconnect transmission connector C.
Check solenoid S3 by measuring the resistance between transmission connector terminal #C3 and the transmission housing. The resistance must be 11-15 ohms.
Other information:
- To disconnect the transmission connector, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Was the resistance OK?
Yes - Checking the wiring
No - Checking the wiring and component
-------------------------------------------------
Checking the wiring
- Ignition off.
Check the cable between control module terminal #A48 (#A48) and transmission connector terminal #C3 (control module side). Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connector, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Was a fault detected?
Yes - Verification
No - Checking the control module
-------------------------------------------------
Checking the control module
- Ignition off
- The breakout box connected
- Connect the control module.
- Transmission connector disconnected
- Ignition on
- Gear selector in position P.
Check the transmission control module (TCM) by measuring the resistance between terminals #A48 (#A48) and #A53 (#A53) on the breakout box. The resistance must be approximately 9 kohms.
Note! When removing the transmission connector, the control module may store diagnostic trouble codes (DTCs) for the gear-shift position sensor, the shift solenoids, the temperature sensor etc.
Try a new control module if the resistance is infinite.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connectors, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM)
- To replace the control module, see Transmission control module (TCM), replacing, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Service and Repair.
Was the resistance OK?
Yes - No Fault Found
No - Verification
-------------------------------------------------
Checking the wiring and component
- Ignition off
- Open the control system.
Check the cable between transmission connector terminal #C3 (transmission side) and the connector for solenoid S3. Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check solenoid S3 by measuring the resistance between the terminal pin on solenoid S3 and the transmission housing. The resistance must be 11-15 ohms.
Remedy as necessary.
Other information:
- To disconnect the transmission connectors, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- To open the control system and to check or replace solenoid S3, see Solenoid control system, replacing Solenoid Control System, Replacing
- To replace the cable harness for the control system, see Cable harness/oil temperature sensor, replacing Removal and Replacement
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Select Continue when the fault has been remedied.
Continue - Resetting the adaptation and oil quality counter
-------------------------------------------------
Resetting the adaptation and oil quality counter
Resetting the adaptation
Resetting adaptation and the counter for "Transmission oil change"
Hint: The transmission has torque controlled adaptive pressure control. Pressure control means that the transmission regulates the pressure itself during each gear shift. This avoids harsh gear shifting. Each gear shift is evaluated by the control module and stored in the memory. This allows for compensation for wear and tear in the transmission and clutch. It is important that the adaptation in the memory is reset after the transmission has been repaired. This is to ensure normal operation. The oil is replaced during repair; the "Transmission oil change" counter must be reset. If the counter is not reset when the fluid is drained and replaced, there is a risk that a diagnostic trouble code (DTC) will be stored in incorrect circumstances.
Note! This applies only if the transmission or one of the components in the transmission have been replaced.
- Ignition on.
Click on the VCT2000 symbol to reset the adaptation and counter.
Continue - Verification
-------------------------------------------------
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off.
- Reinstall the components, reconnect the connectors etc.
- Ignition on.
- Gear selector in position P.
- Activate solenoid S3.
The value should change between OFF and ON.
Does the value change between OFF and ON?
Yes - VERIFIED
No - VERIFICATION FAILED
------------------------
VERIFICATION FAILED - Fault-tracing information
VERIFIED - Fault Found
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - FAULT-TRACING FAILED
No - Attempt New Test
------------------------
FAULT-TRACING FAILED - FAULT-TRACING FAILED
Attempt New Test - Checking the temperature sensor
-------------------------------------------------
Intermittent fault
Check the cable between transmission control module (TCM) terminal #A48 (#A48) and transmission connector terminal #C3. Check for intermittent short-circuit to ground according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults. Check for contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Hint:
- Check the circuit for solenoid S3. Switch off the ignition. Disconnect the control module. Measure the resistance between terminals #A48 (#A48) and #A53 (#A53) on the breakout box. The resistance must be 11-15 ohms.
Remedy as necessary.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connectors, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Select Continue when the fault has been remedied.
Continue - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).
Do you want to view the information again?
Yes - Attempt New Test
No - Fault Found
------------------------
Attempt New Test - Checking the temperature sensor
FAULT FOUND - Fault Found
-------------------------------------------------
Faulty signal
Checking transmission fluid temperature sensor
- Ignition on
- Read off the oil temperature.
Check that the temperature is within its permitted range.
Compare with the transmission temperature.
Was the transmission temperature within its permitted range?
Yes - Intermittent fault
No - Checking transmission fluid temperature sensor
------------------------
Checking transmission fluid temperature sensor
- Ignition off
- Disconnect transmission connector D.
Check the temperature sensor. Measure the resistance between transmission connector D terminals #D7 and #D8.
The resistance must be 4.5-6 kohms at 20°C.
Was the resistance OK?
Yes - Checking transmission fluid temperature sensor
No - Checking the cable and component
------------------------
Checking transmission fluid temperature sensor
Check the cable between control module terminal #A37 (#A37) and transmission connector terminal #D7 (control module side). Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check the cable between control module terminal #A55 (#A55)and transmission connector terminal #D8 (control module side). Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connector, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Was a fault detected?
Yes - Verification
No - Checking the cable and component
------------------------
Checking the cable and component
- Ignition off
- Open the transmission control system.
Check the cable between transmission connector terminal #D7 and temperature sensor terminal #1. Check the cable between transmission connector #D8 and temperature sensor terminal #2. Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Also check the cables for a short-circuit to each other.
Hint: Check the temperature sensor. With the ignition off and transmission connector D disconnected, measure the resistance between transmission connector D terminals #D7 and #D8. The resistance must be 4.5-6 kohms at 20°C.
Remedy as necessary.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connector, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- To open the transmission control system and to check or replace the temperature sensor, see Solenoid control system, replacing Solenoid Control System, Replacing
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Continue - Resetting the adaptation and oil quality counter
------------------------
Resetting the adaptation and oil quality counter
Resetting Transmission fluid change counter
Hint: The transmission control module (TCM) has a counter for the oil quality. The counter counts up if the transmission is exposed to too high a load or an ambient temperature that is too high. If the counter is not reset when the oil is drained or changed, there is a risk that a diagnostic trouble code (DTC) will be stored in faulty circumstances. Therefore it is important that the "Transmission oil change" counter is reset.
Note! This applies only when the transmission fluid is changed and when the fluid is changed when repairs are carried out to the transmission temperature sensor.
- Ignition on.
Reset the counter by clicking on the VCT 2000 symbol.
Continue - Verification
-------------------------------------------------
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off.
- Reinstall the connectors, components etc.
- Ignition on.
- Read off the oil temperature.
Check that the transmission oil temperature is within its permitted range.
Compare with the transmission temperature.
Note! The transmission temperature sensor is located inside the control unit and can be affected by the heat given off by the solenoids.
Is the oil temperature within its permitted range?
Yes - VERIFIED
No - VERIFICATION FAILED
------------------------
VERIFICATION FAILED - Fault-tracing information
VERIFIED - Fault Found
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - FAULT-TRACING FAILED
No - Attempt New Test
------------------------
FAULT-TRACING FAILED - FAULT-TRACING FAILED
Attempt New Test - Checking transmission fluid temperature sensor
-------------------------------------------------
Intermittent fault
Check the transmission control module (TCM) and transmission connector D. Check for contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check the cable between transmission control module (TCM) terminal #A37 (#A37) and transmission connector terminal #D7 (control module side). Check for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check the cable between control module terminal #A55 (#A55)and transmission connector terminal #D8 (control module side). Check for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Remedy as necessary.
Other information:
- To connect the breakout box, see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To disconnect the transmission connector, see Connectors, transmission, disconnecting / connecting, B5244T5, AW55-50/51SN, B5254T2, AW55-50/51SN, B5254T2, AW50/51 AWD Procedures
- For information about signals, see Signal description. Transmission control module (TCM), AW50/51 AWD, AW55-50/51SN Signal Description. Transmission Control Module (TCM).
Continue - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Information
Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).
Do you want to view the information again?
Yes - Attempt New Test
No - Fault Found
-------------------
Attempt New Test - Checking transmission fluid temperature sensor
FAULT FOUND - Fault Found
-------------------------------------------------