TM 5-3805-291-23-1
ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0013 00
THROTTLE POSITION SENSOR CIRCUIT TEST - CONTINUED
5.
Check supply voltage at sensor.
a.
Disconnect connector for throttle position sensor (WP 0039 00).
b.
Turn engine start switch and battery disconnect switch to ON position (TM 5-3805-291-10).
c.
Measure voltage across terminal A (8V supply) and terminal B (digital return) on harness side of connector.
d.
Turn engine start switch to OFF position (TM 5-3805-291-10).
Expected Results. Supply voltage measures 8.0 0.4 VDC at sensor connector.
e.
(1)
If results are OK, correct voltage is measured at sensor connector. sensor is receiving correct supply volt-
age. Proceed to step 6.
(2)
If results are not OK, sensor is not receiving correct supply voltage. Proceed to step 8.
6.
Check signal frequency and duty cycle at sensor.
a.
Install an Adapter, cable, breakout (Item 2, WP 0232 00) Assembly (3-PIN BREAKOUT) at connector for throttle
position sensor.
b.
Remove signal wire from terminal C of connector for throttle position sensor. Remove wire from harness side of
connector.
c.
Turn engine start switch to ON position (TM 5-3805-291-10).
d.
Measure frequency and duty cycle between terminal B (digital return) and terminal C (throttle position) at 7X-
6370 Adapter Cable Assembly (3-PIN BREAKOUT) while you operate throttle pedal.
e.
Turn engine start switch to OFF position (TM 5-3805-291-10).
f.
Remove breakout harness. Restore wires to original configuration.
Expected Results. Frequency is between 150 and 1,000 Hz. Duty cycle is between 7 and 95 percent.
g.
(1)
If results are OK, sensor is producing a valid signal. Proceed to step 7.
(2)
If results are not OK, sensor is not producing a valid signal. Replace throttle position sensor (WP 0039 00).
Verify repair eliminates problem.
7.
Check signal frequency and duty cycle at ECM.
a.
Install a 208-0059 Adapter Cable Assembly (70-PIN BREAKOUT) between J1 and P1 ECM connectors.
b.
Turn engine start switch to ON position (TM 5-3805-291-10).
c.
Measure frequency between terminals P1-66 (throttle position) and P1-5 (digital return) on breakout harness while
you operate throttle pedal.
d.
Measure duty cycle of sensor. Measure duty cycle between terminals P1-66 (throttle position) and P1-5 (digital
return) on breakout harness while you operate throttle pedal.
e.
Turn engine start switch to OFF position (TM 5-3805-291-10).
Expected Results. Frequency is between 150 and 1,000 Hz. Duty cycle is between 7 percent and 95 percent.
f.
(1)
If results are OK, valid signal appears at ECM, but ECM is not reading signal properly. Replace ECM (WP
0057 00). Verify repair eliminates problem.
(2)
If results are not OK, there is not a valid signal at ECM connector. Replace wiring harness in question (WP
0195 00 thru WP 0201 00). Ensure seals are properly in place and connectors are securely connected. Ver-
ify repair eliminates problem.
0013 00-66
