Operation CHARM: Car repair manuals for everyone.

Signal Too High. Intermittent Fault

SIGNAL TOO HIGH. INTERMITTENT FAULT





Checking Cables and Terminals

- Check accelerometer and Engine Control Module (ECM) connectors for loose connections, contact resistance and oxidation.
- Check the cable between accelerometer terminal 1 and engine control module (ECM) #B1 for an intermittent open-circuit.
- Check cable between accelerometer terminal 2 and engine control module (ECM) #B28 for an intermittent open-circuit.
- Check cable between accelerometer terminal 3 and engine control module (ECM) #B32 for an intermittent short-circuit to supply voltage and an intermittent open-circuit.
- The accelerometer power cable is connected inside the engine control module (ECM) to the fuel tank pressure sensor, atmospheric pressure sensor and air conditioning (A/C) pressure sensor power cables. If anything happens to any of these cables all four will be affected. Air conditioning (A/C) pressure sensor wiring is pre-routed, even on cars without one, and should always be checked.

Check Cables Between:

- Accelerometer terminal 1 and engine control module (ECM) #B1.
- Air conditioning (A/C) pressure sensor terminal 3 and engine control module (ECM) #B29.
- Tank pressure sensor terminal 1 and engine control module (ECM) #B15.
- Atmospheric pressure sensor terminal 1 and engine control module (ECM) #B29 for an intermittent short-circuit to ground and an intermittent short-circuit to supply voltage.

- Then proceed to test step below.

Fault-tracing Information

- For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.
- Do you want to repeat fault-tracing?

Yes:
- Return to Checking Cables and Terminals section above.

No:
- Operation done.