DTC Advanced Diagnostics: P16C4
DTC P16C4:Engine Mount Actuator Control Power Circuit Stuck OFF

General Description

The engine mount control system controls the engine mounts electronically. The system consists of the engine mount actuators, the engine mount control unit, and the powertrain control module (PCM). The engine mount control unit uses the crankshaft and camshaft position sensor outputs (received from the PCM) to estimate engine vibration. The engine mount control unit then sends signals to the engine mount actuators to command the engine mounts to push and pull on the engine to counteract engine vibration. The engine mount control unit monitors the engine mount control unit voltage. If the ACM RLY OUT voltage is set value or less for a set time, the engine mount control unit detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Execution
Continuous
Sequence
None
Duration
20 seconds or more
DTC Type
One drive cycle, MIL off
OBD Status
N/A

Enable Conditions
Condition
 
Engine start/stop button
ON mode
No active DTCs set (prevents monitor from running)
P0A14, P0A15, P0AB6, P0AB7, P150A, P150B, P150C, P150D, P150E, P15AB, P15B0, P15BE, P15BF, P15C0, P16C5, P16C6

Malfunction Threshold
The ACM RLY OUT voltage [ACM SOL SUPPLY VOLTAGE] is 4.0 V or less for at least 20 seconds when the active control engine mount (ACM) control relay is on.

[ ]: HDS Parameter

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
Engine mount control unit ACM SOL RLY line open
Engine mount control unit ACM RLY OUT line open
Active control engine mount (ACM) control relay stuck off
Active control engine mount (ACM) control relay line fuse blown
Active control engine mount (ACM) control relay power supply line open
Active control engine mount (ACM) control relay power supply line short to ground
Active control engine mount (ACM) control relay driver line open
Active control engine mount (ACM) control relay driver line short to ground
Engine mount control unit internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.