Operation CHARM: Car repair manuals for everyone.

Current Too Low






Current too low

Checking software




Checking software

Checking software

Note! The information below only applies to modal year 2003-2004.For other model years, select the alternative "No".

It may be possible to remedy the fault by downloading new software into the control module.

Action
- Go to the tab software and program the control module with the latest software.

Other information
- For more information, see Design and Function.





Has the fault been remedied?

Yes - Fault Found

No - No Fault Found

------------------------

FAULT FOUND - Fault Found

No Fault Found - Front heated oxygen sensor (HO2S). Current too low

-------------------------------------------------

Diagnostic trouble code (DTC) status ECM-2100, Front heated oxygen sensor (HO2S). Current too low

Reading off Diagnostic trouble code (DTC) status ECM-2100
Note! When reading off the Diagnostic trouble code (DTC) status, other stored diagnostic trouble codes (DTCs) and their status will be listed.

- 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) displayed as permanent?

Yes - Checking connector

No - Intermittent fault

-------------------------------------------------

Intermittent fault





Current too low. Intermittent fault

Checking wiring and connectors

Caution! Do not apply rust solvent spray or grease to the heated oxygen sensor (HO2S) connector.

Check signal cable (+) between control module #A42 and heated oxygen sensor (HO2S) connector terminal 4 for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check signal cable (-) between control module #A41 and heated oxygen sensor (HO2S) connector terminal 3 for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.

Other information
- Connecting the breakout box/accessing the control module, see
- To access/replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing
- For information about signals, see Signal specification Signal Description / Specification










Continue - Fault-tracing information

------------------------

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

------------------------

Attempt New Test - Checking wiring and connectors

FAULT FOUND - DONE

DONE - DONE

-------------------------------------------------

DONE - DONE

-------------------------------------------------

Checking connector




- Ignition off.
- Check front heated oxygen sensor (HO2S) connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Caution! Do not apply rust solvent spray or grease to the heated oxygen sensor (HO2S) connector.

If wiring is OK, try another heated oxygen sensor (HO2S).

Other information
- To access/replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing






Continue - Checking connector

-------------------------------------------------

Checking connector








- Ignition off.
- Reinstall components, reconnect connectors etc.
- Start the engine and let it idle.
- Read off front heated oxygen sensor (HO2S) signal.
Check that the signal is within its permitted range according to Signal specification Signal Description / Specification.
If signal is now OK this indicates that the fault was caused by poor contact in the connector.

Other information
- To access/replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing.





Is the signal OK?

Yes - Verification

No - Checking wiring and components

-------------------------------------------------

Checking wiring and components

Caution! Do not apply rust solvent spray or grease to the heated oxygen sensor (HO2S) connector.

Check signal cable (+) between control module #A42 (#A42) and heated oxygen sensor (HO2S) connector terminal #4 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Hint: With the ignition on and heated oxygen sensor (HO2S) connector disconnected, the voltage between terminal #4 and ground terminal should be approximately 0.1V.

Check signal cable (-) between control module #A41 (#A41) and heated oxygen sensor (HO2S) connector terminal 3 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If wiring is OK, try another heated oxygen sensor (HO2S).
Remedy as necessary.

Other information
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box
- To access/replace the control module, see
- To access/replace the heated oxygen sensor (HO2S), see Heated oxygen sensor (HO2S), replacing Heated Oxygen Sensor (HO2S), Replacing
- For information about signals, see Signal specification Signal Description / Specification.










Continue - Verification

-------------------------------------------------

Verification




Verification

Verification

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








- Ignition off.
- Reconnect the connectors, reinstall components etc.
- Start the engine and let it idle.
- Read off front heated oxygen sensor (HO2S) signal.
Check that the signal is within its permitted range according to: Signal specification Signal Description / Specification.









Is the signal OK?

Yes - VERIFIED

No - VERIFICATION FAILED

------------------------

VERIFICATION FAILED - Fault-tracing information

VERIFIED - Fault Found

-------------------------------------------------

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

------------------------

FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Front heated oxygen sensor (HO2S). Current too low

-------------------------------------------------