P1146

A : LOW INPUT ON THE VOLTAGE REQUEST SIGNAL WIRE FROM THE ECM (P1146). VEHICLES FITTED WITH 2.5L OR 3.0L ENGINE.

G157288t1 : CHECK THE VOLTAGE REGULATOR REQUEST SIGNAL WIRE FOR A SHORT TO GROUND
1. Disconnect the ECM electrical connector PI1 and the generator electrical connector PI47.
2. Measure the resistance between electrical connector or PI47 pin 1 (YR) and ground.

- Is the resistance less than 10,000 ohms?

-> Yes
REPAIR short to ground between the generator and the ECM. CLEAR the DTC. TEST the system for normal operation.

-> No

G157288t2 : CHECK THE VOLTAGE REGULATOR REQUEST SIGNAL WIRE FOR OPEN CIRCUIT
1. Measure the resistance between electrical connector PI47 pin 1 (YR) and ECM electrical connector PI1 pin 53 (SR).

- Is the resistance less than 5 ohms?

-> Yes

-> No
REPAIR the circuit from the ECM to the generator. CLEAR the DTC. TEST the system for normal operation.

G157288t3 : CHECK THE OPERATION OF THE GENERATOR CHARGE WARNING INDICATOR LAMP
1. Connect the ECM electrical connector PI1 and the generator electrical connector or PI47.
2. CLEAR the DTC. START and RUN the engine at 1500 RPM with no electrical load applied.

- Does the generator charge warning indicator lamp illuminate with in 30 seconds of the engine being started?

-> Yes
INSTALL a new generator. CLEAR the DTC. TEST the system for normal operation. If the DTC is repeated INSTALL a new ECM.

-> No

G157288t4 : CHECK THE OPERATION OF THE GENERATOR CHARGE WARNING INDICATOR LAMP AFTER 15 MINUTES
1. RUN the engine at idle for 15 minutes and then increase engine speed to 1500 RPM for one minute with no electrical load applied.

- Does the generator charge warning indicator lamp illuminate or is DTC repeated?

-> Yes
INSTALL a new generator. CLEAR the DTC. TEST the system for normal operation. If the DTC is repeated INSTALL a new ECM.

-> No DIAGNOSE the ECM.