Hummer H2. Manual - part 168

Test Description 

The numbers below refer to the step numbers on the diagnostic table. 

2: Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a 
total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular 
condition.  

5: Tests for an open in the passlock sensor signal circuit which may not set a DTC B2958 under certain 
conditions.  

6: The presence of DTCs which begin with "U" indicate some other module is not communicating. The 
specified procedure will compile all the available information before tests are performed.  

7: The presence of DTC P0601, P0602, P0604, or P0606 indicates an internal fault in the PCM.  

8: The presence of DTC B1000 indicates an internal module fault.  

9: The Presence of DTC P1637, P1638, P0562 or P0563 indicates a low or high voltage condition.  

Diagnostic System Check - Theft Deterrent 

Step

Action

Yes

No

Schematic Reference:Theft Deterrent System Schematics

1

Install a scan tool. 
Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not 

Power Up in Data Link 

Communications

2

1. Turn ON the ignition, with the 

engine OFF.  

2. Attempt to establish 

communication with the following 
control modules: 

z

Powertrain Control Module 
(PCM)  

z

Body Control Module 
(BCM)  

z

Instrument Panel Cluster 
(IPC)  

Does the scan tool communicate with 
the all the listed control modules?

Go to Step 3

Go to Scan Tool Does Not 

Communicate with Class 2 

Device in Data Link 

Communications

1. Access the Class 2 Power Mode 

parameter in the Diagnostic 
Circuit Check menu on the scan 

IMPORTANT:

Important: The engine may start 
during the following step. Turn OFF 
the engine as soon as you have 
observed the Crank power mode.

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Theft Deterrent - Hummer H2

  

3

tool. 

2. Rotate the ignition switch through 

all positions while observing the 
Class 2 Power Mode parameter.  

Does the Class 2 Power Mode parameter 
reading match the ignition switch 
position for all switch positions?

IMPORTANT:

Insure that all ignition switch 
positions are observed 
including the OFF position.

Go to Step 4

Go to Power Mode 

Mismatch in Body Control 

System

4

Select the display DTCs function on the 
scan tool for the following control 
modules: 

z

Powertrain Control Module 
(PCM)  

z

Body Control Module (BCM)  

z

Instrument Panel Cluster (IPC)  

 
Does the scan tool display any DTCs?

Go to Step 6

Go to Step 5

5

1. Momentarily rotate the ignition 

switch to CRANK. Do not start 
the vehicle.  

2. Release the ignition switch to ON. 

3. With a scan tool, observe the 

Passlock Code in the Body 
Control Module Security Data list. 

Does the scan tool display OPEN?

Go to DTC B2958

Go to Symptoms - Theft 

Deterrent

6

Does the scan tool display any DTCs 
which begin with a "U"?

Go to Scan Tool Does Not 

Communicate with Class 2 

Device in Data Link 

Communications

Go to Step 7

7

Does the scan tool display DTC P0601, 
P0602, P0604, or P0606?

Go to Diagnostic Trouble 

Code (DTC) List in Engine 

Controls - 6.0L

Go to Step 8

8

Does the scan tool display DTC B1000? Go to DTC B1000 in Body 

Control System

Go to Step 9

Does the scan tool display DTC P1637, 

Go to Diagnostic Trouble 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Theft Deterrent - Hummer H2

  

SCAN TOOL DATA LIST 

Body Control Module (BCM) 

9

P1638, P0562 or P0563?

Code (DTC) List in Engine 

Electrical

Go to Diagnostic Trouble 

Code (DTC) List

Scan Tool 

Parameter

Data List

Units Displayed

Typical 

Data Value

Ignition ON/Engine OFF/Vehicle in PARK/Headlamps in AUTO

Auto Learn 
Timer

Security 

Data

Seconds

0-600

Battery 
Voltage

Data

Volts

Varies

Content Theft 
Lamp

Security 

Data

ON/OFF

OFF

Content Theft 
State

Security 

Data

ON/OFF

OFF

Door Unlock 
Switch

Inputs

ACTIVE/INACTIVE

ACTIVE

Driver Door 
Ajar Switch

Inputs

ACTIVE/INACTIVE

ACTIVE 

(door open)

Ignition 1

Inputs

ACTIVE/INACTIVE

ACTIVE

Ignition 3

Inputs

ACTIVE/INACTIVE

ACTIVE

Module Part 
Number

ID 

Information

Numeric

Varies

Passlock Code

Security 

Data

Open/Short/Tamper/Numeric

Valid Code 

1-10

Passlock Data 
Voltage

Security 

Data

Volts

0.86-5 

Volts

Passlock 
Ignition Cycles

Security 

Data

Cycles

Varies

Passlock 
Power

Security 

Data

On/Off

On

Passlock State

Security 

Data

Ignition Off/Tamper/Fail Enable/Fail Enable Dec/Seedkey 

Lrn Pend/Seedkey Learn/Auto Learn Pend/Learn 

Passlock/Monitor Passlock/Normal Decision/Auto Learn

Monitor 

Passlock

Security 
Calibration 
Number

ID 

Information

Numeric

Varies

Security Lamp 
State

Security 

Data

ON/OFF/FLASHING

OFF

Security Suffix

ID 

Information

Two Letters

Varies

Seed and Key 

Security 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Theft Deterrent - Hummer H2

  

Powertrain Control Module (PCM) 

SCAN TOOL DATA DEFINITIONS 

Auto Learn Timer  

The scan tool displays the seconds used by the BCM to learn valid code from the Passlock(tm) sensor. 
The learn procedure consists of 3 consecutive periods. 

Battery Voltage  

The scan tool displays the battery system voltage. 

Content Theft Lamp  

The scan tool displays the state of the SECURITY lamp. The scan tool displays ON when activated by an 
unauthorized entry. 

Content Theft State  

The scan tool displays the state of the content theft feature. The scan tool displays ON when activated by 
an unauthorized entry. 

Door Unlock Switch  

The scan tool displays the state of the door key switch. The scan tool displays ACTIVE when the switch 
is activated in either door key cylinder. 

Drivers Door Ajar Switch  

The scan tool displays the position of the drivers door. The scan tool displays ACTIVE when the drivers 
door is open. 

Ignition 1  

Timer

Data

Seconds

0 Seconds

Tamper Timer

Security 

Data

Seconds

0-600

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition ON/Engine OFF/Vehicle in PARK/Headlamps in AUto

PCM/VCM in VTD Fail Enable

Engine Data 1

Yes/No

No

VTD Auto Learn Timer

Engine Data 1

Active/Inactive

Inactive

VTD Fuel Disable

Engine Data 1

Active/Inactive

Inactive

VTD Fuel Disable Until Ign. OFF

Engine Data 1

Yes/No

No

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Theft Deterrent - Hummer H2