Operation CHARM: Car repair manuals for everyone.

Signal Too High






Signal too high

Status check





Reading off the status of the diagnostic trouble code (DTC)

Engine control module (ECM)

Reading off the status of the diagnostic trouble code (DTC):
Note! When reading off the DTC status, other stored diagnostic trouble codes (DTCs) and their status will also be listed.

- Start the engine. Let it idle for at least 15 seconds.
- Read off the diagnostic trouble code (DTC) status. Check the status of the relevant diagnostic trouble code (DTC).





Was the status of the relevant diagnostic trouble code (DTC) permanent?

Yes - PERMANENT

No - INTERMITTENT

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PERMANENT - Checking the wiring and component

INTERMITTENT - Intermittent fault

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Checking the wiring and component
Check the signal cable between engine control module (ECM) terminals #B31 (#B41) and fuel tank pressure sensor terminal #2. 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.
Check the signal cable between engine control module (ECM) terminal #B4 (#B14) and fuel tank pressure sensor terminal #1. 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.
Check the signal cable between control module terminal #B10 (#B20) and fuel tank pressure sensor connector terminal #3 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 engine control module (ECM) breakout box, see Connecting the breakout box Connecting the Breakout Box
- To access or replace the fuel tank pressure sensor see
- The fuel tank pressure sensor terminal #3 is supplied with approximately 5V. Connector terminal #1 is the ground terminal and connector terminal #2 is the signal
- For information about signals, see Signal specification Signal Description / Specification.










Continue - Verification

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Intermittent fault





Signal too high. Intermittent fault

Checking cables and connectors
Check fuel tank pressure sensor connector for contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check signal cable between engine control module (ECM) connector #B31(#B41) and fuel tank pressure sensor connector #2 for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults and for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check signal cable between engine control module (ECM) control module #B4 (#B14) and fuel tank pressure sensor connector #1 for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults and for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check signal cable between engine control module (ECM) connector #B10 (#B20) and accelerator pedal (AP) position sensor #3 for an intermittent open circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.

Other information:
- For connection of engine control module (ECM) breakout box, see Connecting the breakout box Connecting the Breakout Box.
- To access/replace the fuel tank pressure sensor see the relevant service procedure.
- Voltage supply for the fuel tank pressure sensor #3 is approximately 5 V. #1 is ground terminal and #2 is signal.
- For information about signals, see Signal specification Signal Description / Specification.










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 cables and connectors

FAULT FOUND - DONE

DONE - DONE

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DONE - DONE

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Verification




Verification

Verification

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








- Ignition off.
- Reinstall connectors, components etc.
- Read off fuel tank pressure.
- Start the engine and let it idle.
- Activate the EVAP canister shut-off valve and allow it to open.
Activate canister purge (CP) valve. Open and shut the valve. Read off the fuel tank pressure and check if the values have changed.

Hint: When the canister purge (CP) valve is open the pressure in the fuel tank drops.

Note! If the EVAP canister is full the engine may stop when canister purge (CP) valve activation occurs because of the extra fuel supply.





Does the fuel tank pressure change?

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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Attempt New Test - Status check

FAULT-TRACING FAILED - FAULT-TRACING FAILED

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