U1403-IMPLAUSIBLE FUEL LEVEL SIGNAL RECEIVED


When Monitored:
Ignition on.

Set Condition:
The fuel volume message the ECM is receiving is implausible. The circuit is continuously monitored. One Trip fault.


Possible Causes

CAN B OPEN OR SHORTED

CLUSTER MODULE

TOTALLY INTEGRATED POWER MODULE (TIPM)

ECM



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Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Theory of Operation


The Totally Integrated Power Module isn't receiving a fuel volume signal over CAN B from the Cluster Module. The TIPM has to send the PCM a fuel volume signal over CAN C. The signal the TIPM sends over CAN C is implausible.




Diagnostic Test
1. ACTIVE DTC
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Ignition on, engine not running.
With a scan tool read DTCs.

Is the DTC Active at this time?

Yes

Go To 2


No

Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

2. CAN B BUS HARDWARE DTCS ALSO ACTIVE
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With a scan tool check for DTCs in the FCM (TIPM).

Are any CAN B Hardware related DTCs active at this time?

Yes

(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING) for the appropriate diagnostic procedures.
Perform BODY VERIFICATION TEST – VER 1.


No

Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)