Hummer H1 Service Manual page 1182

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DTC P1654 Check Throttle Circuit
Circuit Description
A dash light is illuminated by the PCM if diagnostics have de-
tected certain errors related to the Accelerator Pedal Position
(APP) sensor. Illumination is accomplished by the PCM pro-
viding a ground path for the light circuit. This is a type D DTC.
Conditions for Setting the DTC
• Check Throttle lamp requested "ON".
• Voltage at the Check Throttle control circuit is greater
than 0 volts.
or
• Check Throttle lamp requested "OFF".
• Voltage at the Check Throttle control circuit is equal to
0 volts.
Action Taken When the DTC Sets
Will not turn "ON" the MIL.
05745159
HOT AT HOT IN RUN
ALL TIMES AND START
FUSE 2D
20 AMP
INTERIOR
C1-10
TO
C29-B3
C28-C13 C28-D13 C28-C12
BATT BATT IGN
GROUND GROUND
C28-D6 C28-D7
HOT AT
ALL TIMES
G2
PCM/Tech 1 Scan Tool 117
HOT IN RUN
AND START
FUSE 3A
20 AMP
EXTERIOR
STS MIL
LAMP LAMP
C10-H
C3-G5
C1-25
C28-C11 C28-D11 C28-C14
IGN STS LAMP
CONTROL CONTROL
SERIAL DATA
59 BK
FUSE 1H
5 AMP
INTERIOR
G4
16
554 GRY
Conditions for Clearing the MIL/DTC
• The PCM will turn the MIL off after three consecutive
trips without a fault condition.
• A History DTC will clear when forty consecutive
warm-up cycles that the diagnostic does not fail (coolant
temperature has risen 5°C (40°F) from start up coolant
temperature and engine coolant temperature exceeds
71°C (160°F) that same ignition cycle).
• Use of a scan.
Diagnostic Aids
A faulty bulb or the control circuit shorted to ground will cause
a P1654 to set.
Test Description
Number(s) below refer to the number(s) on the diagnostic ta-
ble.
2. This test checks the ability of the PCM to command the
Check Throttle lamp on during the bulb check (Check
Throttle lamp should be "ON" for 2 seconds and then go
out).
3. This test will check the control circuit for a short to ground.
6. This test will check the control circuit for an open.
FUSE 4B
5 AMP
INTERIOR
C10-J
STATUS
CENTER
C10-C
C3-F3
C1-28
MIL
POWERTRAIN
CONTROL
MODULE
CLASS II
C28-C8
DLC
4 2
9-S12-064