Signal Too Low

ECM-9540 5 VOLT POWER SUPPLY
SIGNAL TOO LOW

Reading DTC status ECM-9540:




Note! When Reading the DTC status, other stored Diagnostic Trouble Codes (DTCs) and their status will also be listed.

- Read 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 - Skip to "Checking Components and Wiring - Permanent"
No - Continue below.


Checking Component and Wiring - Intermittent



Check cable between engine control module (ECM) # B9 and accelerator pedal (AP) position sensor # 6 for an intermittent short-circuit to ground according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Check cable between engine control module (ECM) # B9 and accelerator pedal (AP) position sensor # 6 for an intermittent open-circuit according to [1][2]Checking Wiring and Terminals. Intermittent Faults

Remedy as necessary.

Other information
- To connect the breakout box, Connecting the Breakout Box (ECM)
- To access/replace the accelerator pedal (AP) position sensor, Accelerator Pedal Module, Replacing
- Before replacing engine control module (ECM), Engine Control Module (ECM), Replacing
- For information about signals, Pinout Values and Diagnostic Parameters


Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
--Testing Complete--


Checking Component and Wiring - Permanent



Check cable between engine control module (ECM) # B9 and accelerator pedal (AP) position sensor # 6 for a short-circuit to ground according to [1][2]Checking Wiring and Terminals. Permanent Fault

Check cable between engine control module (ECM) # B9 and accelerator pedal (AP) position sensor # 6 for an open-circuit according to [1][2]Checking Wiring and Terminals. Permanent Fault

Remedy as necessary.

Other information
- To connect the breakout box, Connecting the Breakout Box (ECM)
- To access/replace the accelerator pedal (AP) position sensor, Accelerator Pedal Module, Replacing
- Before replacing engine control module (ECM), Engine Control Module (ECM), Replacing
- For information about signals, see Diagnostic Parameters and Pinout Values. Pinout Values and Diagnostic Parameters
- Voltage at accelerator pedal (AP) position sensor # 6 should be approximately 5V.


Verification



Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off.
- Reinstall connectors, components etc.
- Ignition on.
Read the analog signal. Try depressing and releasing the Accelerator Pedal (AP).
The value is between 6-9% when the Accelerator Pedal (AP) is unaffected and 80-90% when the Accelerator Pedal (AP) is fully depressed.

Do the values correspond?
Yes - Tesing 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.