PIE0590A

Subject:
Engineering Information - Check Engine Lamp Illuminated On Drivers Information Center (DIC), DTCs U0284, U0285,
P059F and/or P05AE Set
Attention:
Proceed with this EI 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 PIE and proceed with diagnostics found in published
service information. THIS IS NOT A RECALL — refer to Service Bulletin 04-00-89-053 for more details on the use of
Engineering Information bulletins.
This EI has been revised to remove Silverado 1500, Sierra 1500 and add 2020-2021 Silverado 2500HD/3500HD and Sierra 2500HD/3500HD.
Brand:
Chevrolet
GMC
Model:
Model Year:
Silverado 2500HD/3500HD
VIN:
from
to
from
to
2020
2021
-
-
Sierra 2500HD/3500HD
Engine:
Transmission:
Equipped with
6.6L Engine
(RPO L5P and
L8T)
-
Involved Region or Country
North America
Additional Options (RPOs)
Equipped with SHUTTERS-FRONT GRILLE, ACTIVE, UPR AND LWR (RPO WMI)
Condition
Important: If the customer did not bring their vehicle in for this concern, DO NOT proceed with this EI.
Some customers may comment on the check engine lamp being illuminated on the drivers information center
(DIC).
Technicians may find the following DTCs set:
Cause
•
U0284 – Lost Communication with Active Grille Air Shutter 1 Motor Module
•
U0285 – Lost Communication with Active Grille Air Shutter 2 Motor Module
•
P059F – Active Grille Air Shutter 1 Performance
•
P05AE – Active Grille Air Shutter 2 Performance
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.
Correction
If you encounter a vehicle with the above concern, follow the steps that match the DTCs set in the ECM and contact the engineer listed below with your findings:
If DTCs U0284/U0285 are set, follow the steps listed below.
1.
Remove the fascia and ensure that the connectors are properly engaged to the upper and lower aero shutter assemblies, along with the FWD Lamp/Engine
Wire harness to the aero shutter jumper harnesses. If the connectors are not fully engaged, then engage the connectors and cycle the shutters. If the shutters
are functional, no further action is needed. If the problem is not solved, proceed to steps 2 - 7.
2.
Inspect the aero shutter jumper harness for signs of damage and/or corrosion. Take pictures of the damage and/or corrosion areas on the jumper harness.
3.
Check the continuity on each jumper wire harness, upper and lower shutters. Disconnect the FWD Lamp/Engine Wire harness from the shutter assemblies.
4.
Check the continuity on the FWD Lamp/Engine Wire harness.
5.
If step 3 is NOT OK and step 4 is OK, then replace the aero shutter and send the aero shutters to the WPC with the jumper harness attached.
6.
If step 3 is OK and step 4 is NOT OK, then replace/repair the FWD/Engine Wire Harness.
7.
If both step 3 and 4 are NOT OK, then replace aero shutter and repair FWD Lamp/Engine Wire Harness. Send the aero shutters to the WPC with the jumper
harness attached.
If steps 1 - 7 did not address the issue, replace the Aero Shutter and send to WPC with the jumper harness attached.
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If DTCs P059F/P05AE are set, follow the steps listed below.
1.
Check for a foreign object such as a rock, stick or bolt that went through the grille in the upper and lower shutters, that may be stuck in between the
louvers/vanes. If a object is found, please try to remove it from aero shutter assembly if possible. Record and take pictures of removed foreign object.
2.
If no foreign object is found in the aero shutter assembly, cycle the upper and lower aero shutter assemblies. Look for any binding locations and note them if
found.
3.
Check the Outside Air Temperature (OAT) Sensor for the temperature reading and record the value. If recorded value doesn't match actual conditions e.g. 40C° service/repair OAT sensor. Check the OAT sensor temperature value to ensure it is reading accurately, cycle the shutters.
4.
If the aero shutter does not move or is binding after cycling, remove the aero shutter assembly and closely look at the potential binding locations. At this time
if there is any debris that wasn't seen in the aero shutter assembly, remove debris and reconnect the aero shutter assembly back to the vehicle and cycle
shutters. If the shutters DO NOT move, replace the assembly. If there was no debris found, analyze the shutter for disengaged louvers or damage to the
linkage.
If the shutter is replaced, send the shutter to the WPC for engineering analysis. DO NOT remove the jumper wire harness off of the assembly.
Contact Information
The Contact Information has been redacted.
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
If engineer was contacted or required information was provided, use:
Labor Operation
Description
Labor Time
1481438*
Engineering Information - Check Engine Lamp Illuminated On Drivers
Information Center, Multiple DTCs Set
1.2 hr
* This is a unique labor operation for bulletin use only.
Version
2
Modified
Released October 14, 2020
Revised January 12, 2021 – Revised to remove Silverado 1500, Sierra 1500 and add 2020-2021 Silverado
2500HD/3500HD and Sierra 2500HD/3500HD.
2