Signal Missing - Permanent Fault

ECM-3100 ENGINE SPEED (RPM) SENSOR
SIGNAL MISSING - PERMANENT FAULT

Checking connector and wiring



Check engine speed (RPM) sensor connector for contact resistance and oxidation according to [1][2]Checking Wiring and Terminals. Permanent Fault

Check the signal cable between the engine speed (RPM) sensor # 1 and the Engine Control Module (ECM) # A48 (# A48) and between the engine speed (RPM) sensor # 2 and the Engine Control Module (ECM) # A66 (# B6) for a short-circuit to supply voltage according to [1][2]Checking Wiring and Terminals. Permanent Fault, a short-circuit to ground according to [1][2]Checking Wiring and Terminals. Permanent Fault, and for an open-circuit according to [1][2]Checking Wiring and Terminals. Permanent Fault

Check the carrier plate, search for damage and other defects.

Remedy as necessary

Other information
- Connecting the breakout box/accessing the control module Connecting the Breakout Box (ECM)
- To access/replace the engine speed (RPM) sensor, Engine Speed (RPM) Sensor, Replacing
- For information about signals, see Diagnostic Parameters and Pinout Values. Signal Description, ME7, B5XX4T


Verification



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

- Ignition off.
- Reinstall connectors, components etc.
- Start the engine.

If there is a fault in the engine speed (RPM) sensor signal the car will not start.

Does the car start?
Yes - Testing complete.
No - Continue below.


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.