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Faulty Signal






Faulty signal

Checking the load signal




- Start the engine.
- Go into scrolling values.
Read off the load signal.
Normal range idling with the engine at operating temperature, neutral selected and the air conditioning (A/C) off: approximately 35 microseconds. The value increases with engine load.





Does the value increase with engine load?

Yes - Intermittent fault

No - Connecting the breakout box

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Connecting the breakout box





Connecting the breakout box
951 1355 Adapter 42-pin 951 1355 Adapter 42-pin 981 3190 Replaced by 9511428 981 3190 Replaced by 951 1428




Information

Connecting the breakout box to AW50-42





Is the breakout box connected to the control module?

Yes - CONNECTEDReturn to fault-tracing.

No - NOT CONNECTED

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CONNECTED - CONNECTED

NOT CONNECTED - Connecting the breakout box

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Connecting the breakout box




Connecting the breakout box
981 3190 Replaced by 9511428 981 3190 Replaced by 951 1428 951 1355 Adapter 42-pin 951 1355 Adapter 42-pin
Connecting the breakout box

Caution! The voltage supply to the control module must be disconnected when disconnecting the breakout box. Failure to observe this procedure could seriously damage the control module.








- Ignition off
- Expose and disconnect the AW50-42 transmission control module (TCM) according to Replacing the transmission control module (TCM) .
- Control module disconnected.
Connect adapter 951 1355 Adapter 42-pin 951 1355 Adapter 42-pin to the control module connector (wiring side). Connect breakout box 981 3190 Replaced by 9511428 981 3190 Replaced by 951 1428 to the adapter.

Note! Ensure that the adapter is the right way around.









Continue - DONE

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DONE - Checking the ground terminal

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Checking the ground terminal








- Ignition off.
- Control module disconnected.
- Switch off all power consuming equipment, such as courtesy lighting, radio etc.
Connect an ohmmeter between terminal 1 on the breakout box and the battery negative terminal.









The ohmmeter should read approximately 0 ohms.

OK - Return to the fault-tracing procedure where it was interrupted.
No Fault Found

Not OK - Checking for an open-circuit, contact resistance and oxidation

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Checking for an open-circuit, contact resistance and oxidation
Check ground terminal 31/20 and the lead between the ground terminal and control module #1 for open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault and contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.
Check the ground lead between the battery and the body for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault and contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.





Continue - Verification

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Verification




Verification

Hint: After repairs have been completed they must be verified as follows to ensure that the fault has been eliminated:








- Ignition off
- Switch off all power consuming equipment, such as courtesy lighting, radio etc.
- Control module disconnected
Connect an ohmmeter between #1 on the breakout box and the battery negative terminal.









The ohmmeter should read approximately 0 ohms.

OK - VERIFIED

Not OK - VERIFICATION FAILED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should be diagnosed and remedied. Since this is not the case the fault-tracing process has failed.
Complete the fault-tracing for those fault or try again.

Do you want to terminate fault-tracing at this time?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Connecting the breakout box

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CONNECTED - Checking the signal cable for a short-circuit to supply voltage

FAULT FOUND - Checking the signal cable for a short-circuit to supply voltage

FAULT-TRACING FAILED - Checking the signal cable for a short-circuit to supply voltage

No Fault Found - Checking the signal cable for a short-circuit to supply voltage

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Checking the signal cable for a short-circuit to supply voltage








- Ignition off.
- Transmission control module (TCM) connected.
- Ignition on.
Connect an electrician's screwdriver (bulb of at least 3 W) between terminals 23 and 1 on the breakout box.









The electricians screwdriver should not light.

OK - Checking the signal cable resistance to ground

Not OK - Checking for a short-circuit

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Checking for a short-circuit
Check the cable between transmission control module (TCM) terminal 23 and engine control module (ECM) terminal 49 for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.
In cars equipped with the DSA anti-spin system, check the circuit for DSA control module terminal 13 for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.





Continue - Verification

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Checking the signal cable resistance to ground








- Ignition off.
- Engine control module (ECM) disconnected. In cars equipped with the DSA anti-spin system, disconnect the DSA control module according to DSA control module, replacement Service and Repair.
- Transmission control module (TCM) connected.
Connect an ohmmeter between terminals 23 and 1 on the breakout box.









Does the ohmmeter read infinite resistance?

Yes - Checking the signal cable

No - Checking for a short-circuit

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Checking for a short-circuit
Check the cable between transmission control module (TCM) terminal 23 and engine control module (ECM) terminal 49 for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.
In cars equipped with the DSA anti-spin system, check the circuit for DSA control module terminal 13 for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.





Continue - Verification

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Checking the signal cable








- Ignition off.
- Connect the transmission control module (TCM).
- Connect the engine control module (ECM).
- Reconnect the DSA control module according to DSA control module, replacement Service and Repair.
- Start the engine.
- Go into scrolling values.
Read off the load signal.
Normal range idling with the engine at operating temperature, neutral selected and the air conditioning (A/C) off: approximately 35 microseconds. The value increases with engine load.





Does the value increase with engine load?

Yes - Checking contact resistance and oxidation

No - Checking for an open-circuit

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Checking contact resistance and oxidation
The cause of the diagnostic trouble code (DTC) was loose connections in the control module connector. Remedy the transmission connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.





Continue - Verification

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Checking for an open-circuit
Check the cable between transmission control module (TCM) terminal 23 and engine control module (ECM) terminal 49 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.





Continue - Verification

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Verification




Verification

Hint: After repairs have been completed they must be verified as follows to ensure that the fault has been eliminated:




- Ignition off.
- Reconnect the connectors, reinstall components etc.
- Start the engine.
- Go into scrolling values.
Read off the load signal.
Normal range idling with the engine at operating temperature, neutral selected and the air conditioning (A/C) off: approximately 35 microseconds. The value increases with engine load.





Does the value increase with engine load?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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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 - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking the load signal

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Intermittent fault





Faulty signal. Intermittent fault

Intermittent fault
- Check the transmission and engine control module (ECM) connectors for contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring And Terminals. Intermittent Faults.
- Check the cable between the transmission control module (TCM) terminal 23 and engine control module (ECM) terminal 49 for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring And Terminals. Intermittent Faults. Check for a short-circuit to ground according to Checking wiring and terminals. Intermittent faults Checking Wiring And Terminals. Intermittent Faults. Check for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring And Terminals. Intermittent Faults.





Continue - Fault-tracing information

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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

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Attempt New Test - Checking the load signal

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