SB-10045940-3952
File in Section:

Service Bulletin

Bulletin No.:
Date:

PIE0222
August, 2012

ENGINEERING INFORMATION
Subject:

Engineering Information – Blower Motor Inoperative, No HVAC Airflow Through Vents

Models:

2011-2012 Cadillac Escalade, Escalade ESV, Escalade EXT
2011-2012 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2011-2012 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon XL Denali

Attention: Proceed with this PI ONLY if the customer has commented about this concern AND the
PIE number is listed in the Global Warranty Management / Investigate History link
(GWM/IVH). If the customer has not commented about this condition or the EI does not
show in GWM/IVH, disregard the PI and proceed with diagnostics found in published
service information. THIS IS NOT A RECALL — refer to Service Bulletin 04-00-89-053E
for more details on the use of Engineering Information PIs.

Condition
Important: If the customer did not bring their vehicle in for this concern, DO NOT proceed with this EI.
Some customers may comment that the HVAC blower motor is not functioning. They may also comment that there is
no air flow from the HVAC vents. This may be an intermittent condition.

Cause
GM Engineering is attempting to determine the root cause of the above condition. Engineering has a need to gather
information on vehicles PRIOR to repair that may exhibit this condition. As a result, this information will be used to
"root cause" the customer's concern and develop/validate a field fix.

Instructions
Use the following steps to diagnose the condition and, if necessary, replace the affected connector terminal in the
instrument panel junction block. If a terminal is replaced during the repair, save the terminal for engineering analysis.

2062300

1. Remove the cover on the right side of the instrument panel, exposing the junction blocks.

1991088

2. Identify Junction Block X4 and X6.
3. With the ignition key in the on position, turn on the HVAC blower and apply light hand pressure to the
connectors. Determine if this movement affects the blower operation (intermittent operation).
4. Determine which junction block is affecting the blower operation.

Junction Block X4 Correction
Use the following diagnostic and repair steps if the fault is determined to be caused by the X4 junction block.
1. Make sure there are no backed out or loose terminals using the appropriate Terminal Test Probe.

1667399

2.
3.
4.
5.
6.
7.
8.
9.
10.

Locate Pin A6, Circuit 754.
Perform a pin drag test using test probe J-35616-2A (GY).
If the terminal fails the pin drag test, replace the terminal for Pin A6. Refer to Junction Block - Right I/P X4 in SI.
Cut off the terminal between the core and the insulation crimp to minimize any wire loss.
To minimize wire loss, remove only the insulation required.
Position the stripped wire in the terminal.
Hand crimp the core wings first.
Hand crimp the insulation wings around the cable.
Solder the hand crimp terminal.

Junction Block X6 Correction
Use the following diagnostic and repair steps if the fault is determined to be caused by the X6 junction block.
1. Make sure there are no backed out or loose terminals using the appropriate Terminal Test Probe.

493694

2. Locate Pin A, Circuit 542.
3. Perform a pin drag test using test probe J-35616-42 (RD).
4. If the terminal fails the pin drag test, replace the terminal for Pin A. Refer to Junction Block - Right I/P X6 in SI.
5. Cut off the terminal between the core and the insulation crimp to minimize any wire loss.
6. To minimize wire loss, remove only the insulation required.
7. Position the stripped wire in the terminal.
8. Hand crimp the core wings first.
9. Hand crimp the insulation wings around the cable.
10. Solder the hand crimp terminal.
Reconnect the junction block.

Verify the condition has been corrected.
Reinstall the instrument panel right cover.
Save any replaced terminals and contact one of the engineers listed below. Provide the engineer with the steps
taken to correct the condition.

Contact Information
Engineer Name

Phone Number

Jim Resutek

(586) 859-9509

Dave Hayes

(716) 245-1904

Please include the following information if leaving a message:
– Technician name
– Dealer name and phone number
– Complete VIN and repair order (R.O) number
On the repair order, document the date and time the call was placed (even if the engineer was not reached).
If engineering is unable to return the call within one hour, proceed with diagnosis and repair based on information
found in SI.

Warranty Information
For vehicles repaired under warranty, and found to have had the above condition, use:
Labor Operation

Description

Labor Time

N9682*

Diagnose/Repair HVAC Blower Inoperative

0.3 hr

Add

Replace First Junction Block Terminal

0.2 hr

Add

Each Additional Terminal Replacement

0.1 hr

*This is a unique labor operation for bulletin use only. It will not be published in the Labor Time Guide.