TROUBLESHOOTING USING GSC FAULT CODES - Continued
The engine low coolant sensor is powered by 8 Vdc from the GSC. When coolant is present at
the sensor, a logic low (near zero volts) is sent to the GSC. When coolant is not present at the
sensor, a logic high is sent to the GSC.
CID 111 E FMI 03
CID 111 E FMI 04
Engine low coolant sensor.
FMI 03 - Voltage Above Normal.
FMI 04 - Voltage Below Normal.
Set Battery Disconnect Switch to ON. Set DEAD CRANK SWITCH to NORMAL.
On EMCP turn the ENGINE CONTROL switch to COOL DOWN/STOP.
Disconnect ECM to EMCP harness connector ENG-P16 from low coolant sensor
(WP 0090, Figure
2, and FO-2, sheet 2).
Measure the voltage on the ECM to EMCP harness connector between ENG-
P16-A (+) and ENG-P16-B (-). Also measure the voltage between ENG-P16-C
(+) and ENG-P16-B (-).
If the voltage between ENG-P16-A (+) and ENG-P16-B (-) is not 7.5 to 8.5 Vdc or
voltage between ENG-P16-C (+) and ENG-P16-B (-) is not 2.0 to 3.0 Vdc, repair
If repairing or replacing the ECM to EMCP harness does not correct the problem,
If replacing the engine low coolant sensor does not correct the problem, proceed
to STEP 6.
Turn ENGINE CONTROL switch to OFF/RESET. Battery Disconnect Switch is
OFF; DEAD CRANK SWITCH is OFF.