Signal Missing. Permanent Fault

Signal missing. Permanent fault

Checking the connectors








Check the engine speed (RPM) sensor and engine control module (ECM) connectors for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault. Remedy if necessary.
Check in particular for damage or loose terminal pins.
Reconnect the connectors.
Start the engine. Allow the engine to run at idle speed for 30 seconds.
Ignition off for 30 seconds. NOTE! If the engine cooling fan (FC) is running, the ignition must be off for 30 seconds after the engine cooling fan (FC) has stopped.
Start the engine. Allow the engine to run at idle speed for 30 seconds.
Read off the status of the diagnostic trouble code (DTC).





Is the status intermittent?

Yes - Verification

No - Checking the wiring and components

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Checking the wiring and components
Check the engine speed (RPM) sensor resistance. The resistance must be between 250-350 ohms.
Check the signal cables between engine control module (ECM) terminals #24 and #54 and engine speed (RPM) sensor terminals #1 and #2. Check for a short-circuit to ground or supply voltage, for a short-circuit to each other or an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault. Remedy if necessary.

Hint: With the ignition on, the voltage between engine speed (RPM) sensor connector terminals #1 and #2 must be approximately 1.8 V with the reading taken at the ground terminal.

Other information
- To connect the breakout box, see Connecting the breakout box. EMS 2000 Connecting The Breakout Box. EMS 2000.













Was a fault found in the above fault-tracing?

Yes - Verification

No - Defective engine speed (RPM) sensor

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Defective engine speed (RPM) sensor
Try a new engine speed (RPM) sensor according to Replacing engine speed (RPM) sensor Service and Repair.

Select Continue.

Continue - Verification

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Verification




- Start the engine. Allow the engine to run at idle speed for 30 seconds
Ignition off for 30 seconds. NOTE! If the engine cooling fan (FC) is running, the ignition must be off for 30 seconds after the engine cooling fan (FC) has stopped.
Start the engine. Allow the engine to run at idle speed for 30 seconds.
Read off the status of the diagnostic trouble code (DTC).





Is the status intermittent?

Yes - FAULT FOUND

No - No Fault FoundFault-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 - No Fault Found

Attempt New Test - Checking the connectors

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