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Signal Missing






Signal missing

Status check




- Start the engine.
Check that the tachometer is working. Try increasing the engine speed. Check that the tachometer readings are within their permitted range.

Does the engine coolant temperature (ECT) gauge display a faulty value, or a value outside its permitted range?

Yes - Checking components and wiring

No - Checking components and wiring

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Checking components and wiring

Note! In cars with the Melco 2 engine management system, the engine speed (RPM) signal comes directly from the ignition sensor in the engine management system.Diagnostic trouble codes (DTCs) are stored in the engine control module (ECM) if there is a fault in the ignition sensor. These diagnostic trouble codes (DTCs) must be fault-traced first.

Check the signal cable between the engine control module (ECM) and combined instrument panel terminal #B7 (#A37). Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault. Check for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault. 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 for the combined instrument panel,
- To access or replace the combined instrument panel, see Driver information module (DIM), installation/removal, component replacement Driver Information Module (DIM), Installation/Removal, Component Replacement
- For information about signals, see Signal specification Signal Specification.









Select Continue.

Continue - Verification

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Verification




Verification

Verification

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








- Ignition off.
- Reinstall the connectors, components etc.
- Start the engine.
Check that the tachometer is working. Try increasing the engine speed. Check that the tachometer readings are within their permitted range.

Does the tachometer work? Is the value within its permitted range?

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 - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Checking components and wiring

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Checking components and wiring

Note! In cars with the Melco 2 engine management system, the engine speed (RPM) signal comes directly from the ignition sensor in the engine management system.Diagnostic trouble codes (DTCs) are stored in the engine control module (ECM) if there is a fault in the ignition sensor. These diagnostic trouble codes (DTCs) must be fault-traced first.

Check the signal cable between the engine control module (ECM) and combined instrument panel terminal #B7 (#A37). Check for an intermittent 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. Check for intermittent an 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 for the combined instrument panel,
- To access and replace the combined instrument panel, see Driver information module (DIM), installation/removal, component replacement Driver Information Module (DIM), Installation/Removal, Component Replacement
- For information about signals, see Signal specification Signal Specification.









Select Continue.

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 components and wiring

FAULT FOUND - DONE

DONE - DONE

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