TM 9-6115-729-24
0009
TROUBLESHOOTING USING GSC FAULT CODES - Continued
NOTE
The magnetic pickup unit (MPU) on this engine is located at the rear of the engine on the flywheel
housing.
SYMPTOM
27.
CID 190 FMI 02
CID 190 FMI 03
MALFUNCTION
Loss of engine speed signal.
Magnetic pickup unit (engine speed sensor).
FMI 02 - Erratic, Intermittent, or Incorrect Signal.
FMI 03 - Voltage Above Normal.
CORRECTIVE ACTION
STEP 1.
Turn the ENGINE CONTROL switch to OFF/RESET.
STEP 2.
Disconnect connector ENG-P14 from the magnetic pickup unit (MPU) (WP 0090,
Figure 2, sheet 2, and FO-2, sheet 2).
STEP 3.
Measure MPU resistance.
a. If resistance is not 100 to 350 ohms, replace the MPU (WP 0100).
b
If resistance is correct, set DVM to AC volts. Turn DEAD CRANK SWITCH
to CRANK. Measure 2 to 3 Vac on ENG J14-1 to ENG J14-2 (MPU pigtail
connector). Turn DEAD CRANK SWITCH to NORMAL.
(1) If voltage measurement is not OK, adjust the MPU (WP 0100). Verify the
problem is resolved. If not, the MPU is damaged or it is not functioning.
Replace the magnetic pickup unit (WP 0100). Verify the problem is
resolved.
(2) If the voltage measurement is OK, the MPU is functioning OK.
(3) Reconnect ENG-P14 to MPU.
STEP 4.
Disconnect ENG-P37 from the back of the EMCP. Measure resistance between
ENG-P37-1 and ENG-P37-2. Resistance should be 100 to 350 ohms.
a. If resistance is not 100 to 350 ohms, troubleshoot wiring harness between
ENG-P37 of EMCP and ENG-P14 (WP 0090). Repair as necessary
b. If the problem has not been resolved, troubleshoot wiring between EMCP
J37-1 to GSC P7-1 and EMCP J37-2 to GSC P7-2. Repair as necessary
c.
If the problem has not been resolved, check all GSC fuses (FO-4, Sheets 3
and 5).
d. If GSC fuses are ok, replace GSC (WP 0040).
0009-24
