Hummer H2. Manual - part 1267

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Circuit Protection - Circuit Breakers  

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Circuit Protection - Fusible Links  

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Repairing Damaged Wire Insulation  

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Splicing Copper Wire Using Splice Clips  

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Splicing Copper Wire Using Splice Sleeves  

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Splicing Twisted or Shielded Cable  

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Splicing Inline Harness Diodes  

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Heated Oxygen Sensor (HO2S) Wiring Repairs  

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SIR/SRS Wiring Repairs  

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Flat Wire Repairs  

REPAIRING DAMAGED WIRE INSULATION 

If the conductive portion of the wire is not damaged, locate the problem and apply tape around the wire. If the 
damage is more extensive, replace the faulty segment of the wire. Refer to Splicing Copper Wire Using Splice 
Clips and follow the instruction to repair the wire. 

Wire Size Conversion 

FLAT WIRE REPAIRS 

HEATED OXYGEN SENSOR (HO2S) WIRING REPAIRS 

Tools Required 

Metric Wire Sizes (mm 2)

AWG Sizes

0.22

24

0.35

22

0.5

20

0.8

18

1.0

16

2.0

14

3.0

12

5.0

10

8.0

8

13.0

6

19.0

4

32.0

2

50.0

1/0

NOTE:

The flat wire within the flex wiring harness is not serviceable. If an open or short 
exists within the flex wiring harness the complete harness must be replaced.

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Wiring Systems - Hummer H2

  

J-38125 Terminal Repair Kit. See Special Tools and Equipment .

Heated Oxygen Sensor (HO2S) Wiring Repairs 

If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen sensor assembly 
must be replaced. Do not attempt to repair the wiring, connector, or terminals. In order for the sensor to function 
properly it must have a clean air reference. This clean air reference is obtained by way of the oxygen sensor 
signal and heater wires. Any attempt to repair the wires, connectors or terminals could result in the obstruction 
of the air reference and degrade oxygen sensor performance. 

The following guidelines should be used when servicing the heated oxygen sensor: 

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Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors. These 
materials may get into the sensor, causing poor performance. Also, the sensor pigtail and harness wires 
must not be damaged in such a way that the wires inside are exposed. This could provide a path for 
foreign materials to enter the sensor and cause performance problems.  

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Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks, etc., could 
block the reference air path through the lead wire.  

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Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize the 
ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal of the 
ground wire will also cause poor engine performance.  

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To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the vehicle 
harness connector.  

The engine harness may be repaired using the J-38125 . See Special Tools and Equipment . 

SPLICING COPPER WIRE USING SPLICE CLIPS 

Tools Required 

J-38125 Terminal Repair Kit. See Special Tools and Equipment . 

Splicing Copper Wire Using Splice Clips 

1. Open the harness. 

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If the harness is taped, remove the tape.  

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To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.  

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If the harness has a black plastic conduit, pull out the desired wire. 

NOTE:

Do not solder repairs under any circumstances as this could result in the air 
reference being obstructed.

IMPORTANT: When making a splice in an area that may be exposed to moisture use a crimp 

and seal splice sleeve instead of a Splice Clip. Refer to Splicing Copper Wire 
Using Splice Sleeves

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Wiring Systems - Hummer H2

  

2. Cut the wire. 

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Cut as little wire off the harness as possible.  

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Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and 
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.  

3. Select the proper size and type of wire. 

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The wire must be of equal or greater size than the original (except fusible link).  

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The wire's insulation must have the same or higher temperature rating. 

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Use general purpose insulation for areas that are not subject to high temperatures.  

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Use a cross-linked polyethylene insulated wire for areas where high temperatures are 
expected. 

4. Strip the insulation. 

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Select the correct size opening in the wire stripper or work down from the largest size.  

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Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.  

5. Select the proper clip to secure the splice. Follow the instructions in the J-38125 in order to determine the 

proper clip size crimp tool and anvil. See Special Tools and Equipment .  

6. Overlap the 2 stripped wire ends and hold them between thumb and forefinger. 

IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not 

replace cross-linked polyethylene with PVC. 
Cross-linked polyethylene wire is not fuel resistant. Do not use 
to replace wire where there is the possibility of fuel contact.

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Wiring Systems - Hummer H2

  

Fig. 4: Identifying Splice Clip & Stripped Wires 
Courtesy of GENERAL MOTORS CORP. 

7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place. 

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Ensure that the wires extend beyond the clip in each direction.  

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Ensure that no insulation is caught under the clip. 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Wiring Systems - Hummer H2