111
Coolant (COOL) Diagnostic Mode
EFI032
Display: Engine coolant temperature as measured by the
ECT sensor.
DTC: P0116, P0117, P0118, P0119
Usage: Monitor coolant temperature to verify the follow-
ing.
1. ECT sensor signal.
2. High Temperature indicator (on @ 230° F.)
3. Thermostat opening @ approximately 180° F, indi-
cated by a momentary drop or pause in the rising
temperature reading.
4. Left fan ON @ 194° F, OFF @ 185° F; right fan ON
@ 203° F, OFF @ 194° F.
A. fan motor
B. fan relay
C. fan fuse
D. wiring connections
5. High Temperature Rev Limiter 5000 RPM @ 230° F.
Fuel Sensor (FUEL) Diagnostic Mode
EFI031
Display: Fuel level signal from the fuel level sensor
(measured in ohms).
DTC: C1400, C1401, C1402
Usage: Check output of the fuel level sensor.
1. Full fuel is indicated by a reading of 86-100 ohms.
2. Empty is indicated by a reading of 0-5 ohms.
* 110-500 ohms, suspect the fuel level sensor or wiring
* 0-100 ohms but no fuel gauge indication, suspect the fuel gauge
Tachometer (tACH) Diagnostic Mode
EFI030
Display: Engine RPM
DTC: P0336, P0337, P0339
Usage: Verify engine speed signal from the following.
1. CKP (crankshaft position) sensor to ECM
2. ECM (CAN) signal to gauge (tachometer)
3. ECM (CAN) signal to EPS
Speed (SPd) Diagnostic Mode
EFI029
Display: Vehicle speed signal.
DTC: P0500
Usage: Verify speedometer sensor signal from the fol-
lowing.
1. Speed sensor to ECM.
2. ECM (CAN) signal to gauge (speedometer/odometer).
3. ECM (CAN) signal to EPS unit.