Signal Too Low

Signal too low

Checking components
Check that the engine speed (RPM) sensor is correctly installed.
Check the engine speed (RPM) sensor connector. Check for intermittent contact resistance and oxidation.

Hint: The engine speed (RPM) sensor and its wiring are sensitive to interference from surrounding cables, the starter motor cable for example, or similar high amperage cables.

Interference can cause difficulty in starting the engine, prevent the engine from starting at all or cause the tachometer to flicker during start attempts etc.

Causes of interference can be:
- nearby cables, such as an incorrectly routed cable for the starter motor
- incorrectly tightened bolted joints securing the transmission to the engine.

Checking power cable
Check for incorrectly routed cables (routed too close to the engine speed (RPM) sensor).

Checking bolted joints
When removing and installing the transmission it is important that all the bolts for the engine are correctly tightened. Incorrectly tightened bolts can cause poor ground connection and interfere with the engine speed (RPM) sensor. Check that all the bolts from the transmission to the engine are correctly tightened.

Checking the wiring
Check the signal cable between the engine speed (RPM) sensor terminal #1 and engine control module (ECM) terminal #A48 (#A48) and between the engine speed (RPM) sensor terminal #2 and engine control module (ECM) terminal #A66 (#B6). Check for an intermittent short-circuit to supply voltage. Check for an intermittent short-circuit to ground. Check for an intermittent open-circuit.

Other information:
- Checking wiring and terminals Checking Wiring And Terminals
- Engine speed (RPM) sensor, replacing Service and Repair.
Remedy as necessary.









Continue - Verification

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Verification




Verification

Verification

Hint: After carrying out the repair, check that the fault has been remedied.








- Ignition off
- Reconnect the connectors, reinstall components etc.
- Start the engine
- Read off the diagnostic status and fault status for the diagnostic trouble code (DTC) by selecting the relevant diagnostic trouble code (DTC) from the list.
Increase the engine speed a number of times until the diagnostic is "Complete".
Check the fault status for the diagnostic trouble code (DTC) when the diagnostic is "Complete". If the function is correct, the fault status must be "No fault found" when the diagnostic is complete.

Hint: In some cases several functions of the component will be diagnosed. The affects the amount of time taken to run the diagnostic.





Is the function OK?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - Fault Found

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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 - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking components

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