Most of the warning lights and fuel gauge does not operate when the ignition switch is turned to on.
Given the complexity of your vehicle , all the control modules , serial data communication network. Having the vehicle scanned for DTC'S - diagnostic trouble codes , not a code reader or at a auto parts store . A professional type tool is need to pull codes from BCM - body computer , Instrument cluster .
The IPC displays the fuel level as determined by the PCM. The body control module (BCM) receives a class 2 message from the PCM indicating the fuel level percent. The BCM converts the fuel level percent into a percent gage deflection. The IPC receives a message from the BCM via the serial peripheral interface (SPI) indicating the requested gage position. The fuel gage defaults to E (empty) if:
• The PCM detects a malfunction in the fuel level sensor circuit.
• The BCM detects a loss of class 2 communications with the PCM.
• The IPC detects a loss of SPI communications with the BCM.
When the fuel level is less than a pre-determined value, the low fuel indicator illuminates.
Could have U- codes , communication network problems .
DTC U1000 and U1255
Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the ID number of the module which sent the message for State of Health monitoring, Node Alive messages. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. When a module does not associate an ID number with at least one critical parameter within about 5.5 seconds of beginning serial data communication, DTC U1000 or U1255 is set. When more than one critical parameter does not have an ID number associated with it, the DTC will only be reported once.
The table below list the modules on the Class 2 Serial Data Circuit that will set a U1000 or U1255 and should be actively communicating the previously described messages on the Class 2 Serial Data Circuit.
Mar 08, 2017 |
2003 Chevrolet Malibu