B1556
CIRCUIT DESCRIPTIONThe instrument panel cluster (IPC) uses no external circuits for the operation that sets this DTC. The IPC stores 3 redundant copies of the vehicle odometer mileage within the EEPROM. The 3 EEPROM mileage records stored mileage records must agree.
CONDITIONS FOR RUNNING THE DTC
The diagnostic test is performed once every 0.3 seconds during normal running mode and service diagnostics mode.
CONDITIONS FOR SETTING THE DTC
The 3 redundant copies of the vehicle odometer mileage within the EEPROM do not agree.
ACTION TAKEN WHEN THE DTC SETS
^ The IPC displays the word ERROR in the odometer display
^ The odometer will not operate.
^ The trip odometer is not affected.
CONDITIONS FOR CLEARING THE DTC
^ A current DTC clears when the malfunction is no longer present.
^ A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.
DIAGNOSTIC AIDS
^ This DTC may be stored as a history DTC with out affecting the operation of the module. If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.
^ This DTC will never set as current during testing unless there is a non-recoverable memory failure.
^ Intermittent interruptions to either the Hot At All Times supply or the processor ground will cause the module to set the DTC.
^ If this DTC is retrieved as both a current and history DTC, replace the module.
TEST
