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Multiplex Wake-Up Test

Multiplex Wake-up Test




1. From the sleep mode. Wake-up the multiplex system by performing one of the above operations:
2. As the system shifts to its active (wake-up) mode, communication wire voltage will return to 4 - 10 V and the battery terminal current will return to 70 - 80 mA.
3. If the system does not go into sleep mode or wake-up properly, perform the Multiplex Control Unit Input Test.

NOTE: If multiplex circuits fail to respond in the Mode 2 tests and/or the multiplex circuit fails to go into sleep mode or wake-up, it may mean that a control unit failed without triggering a DTC in Mode 1. Perform the Multiplex Control Unit Input Test. If the input test confirms that all the inputs are working properly, substitute a known-good multiplex control unit, gauge assembly or ECM one at a time. If after swapping one of the above components the system works properly, replace the original component, it is faulty.