2003 yukon xl 1500 "service air bag"

Have to have a repair shop retrieve the codes & diagnose
the SRS System

THis information from TS Bulletin...

Subject: "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra, Avalanche, Suburban, Tahoe, Yukon, Yukon XL)
with Four Wheel Drive and NVG 236/246 Transfer Case (RPO NP8)

Condition: Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the technician may find DTC B2725 set.

Cause: The condition may be due to a intermittent fault in the transfer case shift control switch.

Correction:
Important: The transfer case shift control module should not need replacement. DO NOT replace P/N 15749703 unless diagnosis points to the module as the malfunction.

Replace the transfer case shift control switch using published Service Information procedures.

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check brake fluid level first- if low add , second - look at wheels - if a lot of black/brown buildup on wheel- wheel cylinder could be leaking- warning lights tend to come on for a fluid problem

{: ) The a/c air filter is located below the glovebox. Looking from beneath, you will find the front blower motor, next to left is the blower resistor, and then next to its left you'll find a long rectangular cover screwed at both ends. Remove the screws then the cover. Pull and slide the air filter out of the HVAC slot and note the original positioning, so you wont be lost when you insert the new air filter.

jeeze, so many "common" causes. but THE most likely cause is an oxygen sensor out of range. replacing same and driving several miles might get you lucky and save some money. but note, a restricted fuel or air filter will likewise make this sensor report bad data and set the same code. in other words, don't ignore maintenance issues...

Probably not, the code readers they use are meant for emissions.

The airbag connectors in behind the front kick panels have high resistance. The fix is to replace them. Here is TSB's

#05-09-41-001B: Supplemental Inflatable Restraint (SIR) Light ON, Diagnostic Trouble Codes (Inspect/Replace IP Harness to Inflatable Restraint Module (Air Bag) Yellow 4-Way Connector C221 and/or C222) - (Jun 2, 2008)

Subject:
Supplemental Inflatable Restraint (SIR) Light ON, Diagnostic Trouble Codes (DTC) B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 (Inspect and/or Replace IP Harness to Inflatable Restraint Module (Air Bag) Yellow 4-Way Connector C221 and/or C222)

Models:
2003-2006 Cadillac Escalade Models
2003-2006 Chevrolet Avalanche, Suburban, Tahoe
2003-2007 Chevrolet Silverado (Classic Only)
2003-2006 GMC Yukon, Yukon XL, Yukon Denali, Yukon Denali XL
2003-2007 GMC Sierra (Classic Only)

This bulletin is being revised to add the 2007 model year for pickups and change a part number. Please discard Corporate Bulletin Number 05-09-41-001A (Section 09 -- Restraints).

Condition
Some customers may comment that the Service Supplemental Inflatable Restraint Light is on.

Diagnosis with a scan tool may indicate a DTC B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044.

Cause
The most likely cause of any one of the following DTCs: B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 is improper connection/high resistance in the IP harness to inflatable restraint module connector C221 and/or C222.

Diagnostic Information
DTC B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 will set when one of the following conditions occur:
• The SDM detects the air bag module deployment loop resistance is greater than 4.8 ohms for 500 milliseconds.
• The SDM detects that the voltage at the air bag module high control is less than 2.4 volts and deployment loop resistance is 6 ohms or greater for 500 milliseconds.
• For additional diagnostic information, refer to DTC B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 in the appropriate SI Document.

Correction

DO THIS
Test for proper connection/high resistance at connector C221 and/or C222.

Don't Do This
DO NOT replace SIR system components prior to testing for proper connection/high resistance in C221 and/or for DTCs B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044.

Caution: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling Zones. Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs.

Important: The IP harness to inflatable restraint module connectors C221 or C222 is NOT located at the base of the steering column...
• C221 (4 Cavities) -- I/P Harness to Body Harness, behind the left kick panel
• C222 (4 Cavities) (w/o HP2) -- I/P harness to body harness, behind the right kick panel
• C222 (4 Cavities) (w/HP2) -- Behind the left side I/P access panel
• Refer to the Master Electrical Component List for additional location information.

1. Remove the appropriate side door sill plate.
2. Remove the appropriate side hinge pillar panel.
3. Locate the IP harness to inflatable restraint module yellow 4-way connector C221 or C222.
4. Inspect the IP harness to inflatable restraint module connector C221 or C222 for proper connection.
5. Disconnect and reconnect the IP harness to inflatable restraint module connector C221 or C222 THREE times.
6. Clear the DTC and road test the vehicle.
• If DTCs B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 DOES NOT reset, no additional repairs are necessary. Continue with step 10.
• If DTCs B0013, B0014, B0017, B0018, B0024, B0026, B0043, B0044 DOES reset, the most likely cause is high resistance in the IP harness to inflatable restraint module connector C221 or C222. Continue with the next step.
7. Replace the appropriate connector C221 and/or C222, P/N's 15306186 and 88987998. Refer to SIR/SRS Wiring Repairs (SI Document ID #325229).
8. Road test the vehicle and confirm that the repair is complete.
9. Install the driver's side hinge pillar panel.
10. Install the driver's side door sill plate.

Parts Information
Part Number: 15306186
Description: Connector (4-way Female, w/Leads) - Qty 1

Part Number: 88987998
Description: Connector (4-way Male, w/Leads) - Qty 1


Hope this help (remember comment and rated this help).

First get the codes from the transfer case control module.This will help in diagnosing the problem.You can try pushing the 2hi and 4lo buttons simultaneously for 10 seconds.This should put the transfer case in neutral. Then try going to 2 hi.See if this will get it out of 4wd.Let me know what you find.If you need more help let me know Good luck.

leaking suspension air bags is the most common cause, but the system can be tested for trouble codes, I suggest u do so, only the dealer can do this, but guessing about what the problem is can get very expensive very fast.

Sounds like the sensor is tripped due to low pressure in the compressor you have to get the unit charged and the light will go off. Or take it to a auto parts store and have them put their diagnostic code reader on their and have them clear the codes this may fix it as well