Hummer H1 Service Manual page 1115

50 PCM/Tech 1 Scan Tool
DTC P0220 Accelerator Pedal Position (APP)
Sensor 2 Circuit
Circuit Description
The Accelerator Pedal Position (APP) module provides a volt-
age signal that changes relative to accelerator position. There
are three sensors located within the APP module that are scaled
differently. This is a type C DTC.
Conditions for Setting the DTC
• Reference voltage on APP 2 less than 4.8 volts.
• Condition met for 2 seconds.
Action Taken When the DTC Sets
If DTC P0220 is stored, the PCM will turn "ON" the "Service
Throttle Soon" lamp and limit power.
Conditions for Clearing the MIL/DTC
• 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 Tool
Diagnostic Aids
The most likely cause of this DTC is loose connectors or termi-
nals. All 5 volt reference circuits must be checked for proper
reference voltage. Volt meter accuracy is important.
_____________________________________________________
ACCELERATIOR
PEDAL POSITION
SENSOR
44
D B
32
C
2
53
G A
17
F
1
60
E J
15
K
3
14
20
HOT IN RUN 22
AND START
C1
FUSE 3A
10 AMP
EXTERIOR
C5-A4
A
RESUME
ACCEL
HOT IN RUN
AND START
SET
COAST
FUSE 5C
10AMP
INTERIOR B
ON/
OFF
295 BR
POWERTRAIN
CONTROL
MODULE
(PCM)
722 PP C29-A12
721 LB C27-C5
719 BR C29-B1
718 DB C29-B2
725 GY C27-D6
724 DG C27-D4
723 YL C27-D3
717 WH C27-D12
720 TN C28-C2
C5-D3
B
154 TN C28-D14
C
37 C27-D10
YL 153 LG
D
42
C29-B11
GRN 152 DB
A 29
RD 151 GY C29-A11
C1
Test Description
Number(s) below refer to the number(s) on the diagnostic ta-
ble.
2. This step will determine if there is a good voltage reference.
GROUND
APP 2
SIGNAL
GROUND
APP 1
SIGNAL
GROUND
APP 3
SIGNAL
5 VOLT
REFERENCE
WASTEGATE
SOLENOID
CONTROL
RESUME
ACCEL
SIGNAL
SET
COAST
SIGNAL
ON / OFF
SIGNAL
9-S12-055
®