Pinpoint Test E: The ACM Illumination Is Inoperative

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

E1 CHECK THE ACM ILLUMINATION CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Disconnect: ACM C240b.
- With the parking lamps on, rotate the instrument panel dimmer switch to the full illumination position.
- Measure the voltage between the ACM C240b-14, circuit 29S-LK34 (OG/BK), harness side and ground.
  
  Fig 1: Measuring Voltage Between ACM C240B-14, Circuit 29S-LK34 (OG/BK), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to E2 .
- No : REPAIR circuit 29S-LK34 (OG/BK) for an open. TEST the system for normal operation.
E2 CHECK FOR CORRECT ACM OPERATION
- Disconnect all the ACM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the ACM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new ACM . REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.