Hummer H2. Manual — part 1116
DIAGNOSTIC INFORMATION AND PROCEDURES
DIAGNOSTIC STARTING POINT - ENGINE ELECTRICAL
Begin the system diagnosis with the Diagnostic System Check - Engine Electrical . The Diagnostic System
Check will provide the following information:
z
The identification of the control module(s) which command the system.
z
The ability of the control module(s) to communicate through the serial data circuit.
z
The identification of any stored diagnostic trouble codes (DTCs) and their status.
The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and
where the procedure is located.
DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL
Diagnostic System Check - Engine Electrical
A
BN
4
Accessory Voltage
B
RD/WH
342
Battery Positive Voltage
C
PK
3
Ignition 1 Voltage
D
YE
5
Crank Voltage
E
WH
1390
Acc/Run/Crank Voltage
F
RD
142
Battery Positive Voltage
G
OG
300
Ignition 3 Voltage
Step
Action
Yes
No
1
Did you perform the Battery Inspection/Test?
Go to Step 2
Go to Battery
Inspection/Test (Non-HP2)
2
Install a scan tool.
Does the scan tool power up?
Go to Step 4
Go to Scan Tool Does Not
Power Up
3
1. Access the Class 2 Power Mode in the
Diagnostic Circuit Check on the scan tool.
2. Rotate the ignition switch through all
positions while observing the ignition
switch power mode parameter.
Does the ignition switch parameter reading
match the ignition switch position for all switch
positions?
IMPORTANT:
The engine may start during the following
step. Turn OFF the engine as soon as you
have observed the Crank power mode.
Go to Step 4
Go to Power Mode
Mismatch in Body Control
System
2004 Hummer H2
2004 ELECTRICAL Engine Electrical - Hummer H2
SCAN TOOL DATA LIST
Powertrain Control Module (PCM)
SCAN TOOL DATA DEFINITIONS
4
1. Turn ON the ignition, with the engine
OFF.
2. Attempt to communicate with each
module on the class 2 serial data circuit.
If using a Tech 2, obtain this information
using the Class 2 Message Monitor
feature.
Does the scan tool communicate with any
module on the class 2 serial data circuit?
Go to Step 5
Go to Scan Tool Does Not
Communicate with Class 2
Device
5
1. Select the Display DTCs function for each
module.
If using a Tech 2, use the Class 2 DTC
Check feature in order to determine which
modules have DTCs set.
2. Record all of the displayed DTCs the
DTC status and the module which set the
DTC.
Does the scan tool display any DTCs?
Go to Step 6
Go to Symptoms - Engine
Electrical
6
Does the scan tool display any DTC beginning
with "U"?
Go to Diagnostic
Trouble Code
(DTC) List
Go to Step 7
7
Does the scan tool display any DTC beginning
with "P"?
Go to Powertrain
DTC list in Engine
Controls
Go to Step 8
8
Does the scan tool display any DTC beginning
with "B"?
Go to Diagnostic
Trouble Code
(DTC) List
Go to Diagnostic Trouble
Code (DTC) List
Scan Tool Parameter
Data List
Units Displayed
Typical Data Value
Ignition ON/Engine OFF
Ignition 1 Signal
Engine 1,2 Data
Volts
9-14v
GEN L-Terminal Signal Command
Engine 2 Data
OK/No Output
OK
GEN F-Terminal Signal
Engine 2 Data
%
10-90%
2004 Hummer H2
2004 ELECTRICAL Engine Electrical - Hummer H2
Ignition 1 Signal
The scan tool displays the current voltage at the battery.
GEN L-Terminal Signal Command
The scan tool displays OK/No Output. The scan tool displays OK until malfunction is detected on the
generator L terminal circuit, then it reads No Output.
GEN F-Terminal Signal
The scan tool displays 0%-100%. The scan tool displays 0%-5% until the engine is running, then the
percentage value varies depending on electrical loads.
DIAGNOSTIC TROUBLE CODE (DTC) LIST
Diagnostic Trouble Code (DTC) List
DTC B1327
Circuit Description
All vehicle modules monitor system voltage. The system voltage message is sent to other modules via Class 2
message. When the system voltage drops below the specified range DTC B1327 shall set within the affected
module.
Conditions for Running the DTC
This DTC shall run only if the module has power, ground and the ignition is not in START mode. This DTC
shall execute regardless of the battery voltage, except when the DTC B1390 is set current.
Conditions for Setting the DTC
z
This DTC shall be set as current when the voltage falls below 9.0 volts for 1.2 seconds.
z
When the vehicle exits START the module shall delay checking the voltage for 2 seconds.
Action Taken When the DTC Sets
DTC
Diagnostic Procedure
Modules
B1327
DTC B1327
BCM
B1328
DTC B1328
BCM
P0562
DTC P0562
PCM
P0563
DTC P0563
PCM
P1637
DTC P1637
PCM
P0622
DTC P0622
PCM
P0615
DTC P0615
PCM
2004 Hummer H2
2004 ELECTRICAL Engine Electrical - Hummer H2
z
A message shall be sent out on the class 2 lines to notify all other modules of low battery voltage.
z
The modules disable the setting of U codes and other DTCs.
Conditions for Clearing the DTC
z
The DTC will clear current status when the voltage is greater than 9.5 volts for 1.2 seconds.
z
A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no
longer present.
z
Use the ON-Board clearing DTCs feature.
z
Use a scan tool.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
3: Tests for the proper voltage at battery positive voltage sense circuit of the module, if voltage is not
within the proper operating range, the voltage sense circuit needs to be tested.
4: Tests the circuit for high resistance.
5: Tests for the proper ground circuit for the module.
DTC B1327
Step
Action
Value
(s)
Yes
No
Schematic Reference:Starting and Charging Schematics or Power Distribution Schematics in
Wiring Systems
Connector End View Reference:Master Electrical Component List in Wiring Systems
1
Did you perform the Engine Electrical Diagnostic System
Check?
-
Go to
Step 2
Go to Diagnostic
System Check -
Engine Electrical
2
1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, observe the battery voltage parameter
in the affected module data list. Or with a DMM,
measure the battery voltage at the appropriate circuit of
the module.
Does the voltage measure greater than the specified value?
9.4 V
Go to
Step 6
Go to Step 3
3
1. Turn OFF the ignition.
2. Disconnect the harness connector of the module setting
the DTC B1327.
3. Measure the voltage between the battery positive
voltage circuit of the module setting the DTC B1327
and the ground circuit of the module setting the DTC
9.4 V
2004 Hummer H2
2004 ELECTRICAL Engine Electrical - Hummer H2
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст