Symptom List:
P1681-ACM CIRCUIT FAULT
P1681-ACM CIRCUIT SHORT TO VOLTAGE
Test Note:
All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P1681-ACM CIRCUIT FAULT.
POSSIBLE CAUSES
AIRBAG CONTROL MODULE
INTERMITTENT CONDITION
ACM SIGNAL CIRCUIT SHORTED TO VOLTAGE
ENGINE CONTROL MODULE
TEST
ACTION
APPLICABILITY
1
NOTE: If the ECM detects and stores a DTC, the ECM also stores the
engine/vehicle operating conditions under which the DTC was set. Some of
these conditions are displayed on the DRB at the same time the DTC is
displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to
duplicate these conditions may assist when checking for an active DTC.
With the DRB, check the Airbag Module for proper communication and DTCs. If
there are any ACM DTCs, repair them prior to continuing this test.
Turn the ignition on.
With the DRB, erase ECM DTCs.
Start the engine.
With the DRB, read ECM DTCs.
Did this DTC set again?
All
Yes
→ Go To 2
No
→ Go To 4
2
Turn the ignition off.
Disconnect the ECM harness connectors.
Remove the Engine Control Relay.
Connect a jumper wire between cavity 30 and cavity 87 of the Engine Control Relay
connector.
Turn the ignition on.
Measure the voltage of the ACM Signal circuit.
Is the voltage below 1.0 volt?
All
Yes
→ Replace the Engine Control Module in accordance with the
Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No
→ Go To 3
104
DRIVEABILITY - DIESEL