Circuit/System Testing

Verify DTC P0562 is set as current.
- If the DTC is history, refer to Charging System Test .
Engine running, measure the voltage at the battery terminals and compare it with the Ignition 1 Signal parameter. Verify that battery terminal and Ignition 1 signal readings do not differ more than 2 volts.
- If greater than the specified value, test the Ignition 1 and ground circuits for open/high resistance.
  - Ignition 1 signal 3.5L and 3.9L engine X1 terminal 19 and X1 terminal 47
  - Ignition 1 signal 5.3L engine X1 terminal 19 and X2 terminal 13
  - Ground circuit 3.5L and 3.9L engine X1 terminal 73
  - Ground circuit 5.3L engine X2 terminal 73
If the circuits test normal, replace the ECM.