ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
INJECTOR SOLENOID CIRCUIT TEST - CONTINUED
Verify ECM detects a short circuit for suspect injector:
WARN I N G
Do not touch jumper wire during test. A strong electrical shock hazard is present at jumper wire while test
is running. Failure to follow this warning may result in injury to personnel or damage to equipment.
Connect jumper wire to engine ground stud.
Place battery disconnect switch in ON position (TM 5-3805-291-10).
Perform injector solenoid test at least two times.
Place battery disconnect switch in OFF position (TM 5-3805-291-10).
ET displays "Short" for two injectors that share supply wire.
Expected Results. ET displays correct status for each test circuit.
If results are OK, ECM detects correct status of circuit. There is an open circuit or a short circuit in engine
harness. There may be a problem with a connector. Replace wiring harness in question (WP 0195 00 thru
WP 0201 00). Ensure seals are properly in place and connectors are securely connected. Verify repair elim-
If results are not OK, ECM does not detect correct status of circuit. There is a problem with ECM. Replace
ECM (WP 0057 00). Verify problem is resolved.
THROTTLE POSITION SENSOR CIRCUIT TEST
System Operation Description:
Use this procedure to troubleshoot any suspected problems with circuit for throttle position sensor. This procedure
covers these diagnostic codes:
41-03 8 Volt DC Supply Short to +Batt
41-04 8 Volt DC Supply Short to Ground
91-08 Throttle Position Signal Abnormal
Throttle position sensor provides throttle signal to ECM. Throttle position sensor is mounted to a pedal assembly
that allows operator to control engine speed. Geometry of pedal assembly controls both travel of sensor and range
of output signal. Throttle position sensor cannot be adjusted.
Output from throttle position sensor is a PWM signal that varies with position of throttle pedal. Throttle position
sensor produces a minimum duty cycle in released position and a maximum duty cycle in fully depressed position.
When pedal is released, ECM translates sensor's output signal to a throttle position of 0 percent.
When pedal is fully depressed, ECM translates output signal to a throttle position of 100 percent.
Throttle position sensor is powered by 8.0 ± 0.4 VDC provided by ECM. A digital return for sensor is also pro-
vided by ECM.