NHTSA ID Number: 10224850
Manufacturer Communication Number: 21-NA-006
Summary
This bulletin provides a possible location of a bad connection at the reductant fluid tanks electrical connector.
Condition
Some customers may comment that the MIL is illuminated and a reduced power message with a Service Emissions System message as well.
Some technicians may one or more of the following DTCs set in the Engine Control Module (ECM):
- P20C1: Reductant Heater 3 Control Circuit
- P21DD: Reductant Tank Heater 1 Low Current
- P221C: Reductant Tank Heater 2 High Current
- P10D9: Reductant Heater 1 Control Circuit Shorted
- P10F3: Reductant Heater 2 Control Circuit Shorted Reductant Heater 2 Control Circuit
- P143C: Reductant Heater 3 Control Circuit Shorted Reductant Heater 2 Control Circuit
- P20B9: Reductant Heater 1 Control Circuit
- P221E: Reductant Tank Heater 3 Low Current
Some technicians may also find when commanding one of the heaters on, that there is no current, 0 amps in GDS2 or unable to command the heaters on.
Cause
This condition may be caused by a poor connection at the Emission Reduction Fluid Tank electrical connector.
Correction
Inspect the A38 – Reductant Pump and Sensor Assembly electrical connector for any signs of damage and repair as necessary.
– If this condition is not found, refer to Service Information section.
Note: If this condition is found on a Silverado HD or Sierra HD, check for an update to the Emissions Reductant Fluid Controller. Updating the controller will prevent this from happening again.
Service Information
On all vehicles, replace the Emission Reduction Fluid Tank Replacement in SI.
Parts Information
| Description | Part Number | Qty |
| L5P: TANK, EMIS RDCN FLUID (INCLS 3,5-10) CK209,309 (43- 53) (L5P) 2020 – 2022 01 8D 5305A | 85138746 | 1 |
| LM2 P/U: TANK, EMIS RDCN FLUID CK105, 107 (43) (LM2) 2020 – 2022 01 8D 5305B | 84914535 | 1 |
| LM2 SUV: TANK, EMIS RDCN FLUID CK1 (06) (LM2) 2021 – 2022 01 8D 5305B | 86772598 | 1 |
28 Affected Products
Vehicles
| MAKE | MODEL | YEAR |
CADILLAC | ESCALADE | 2021-2022 |
| CADILLAC | ESCALADE ESV | 2021-2022 |
| CHEVROLET | SILVERADO 1500 | 2020-2022 |
| CHEVROLET | SILVERADO 2500 | 2020-2021 |
| CHEVROLET | SILVERADO 3500 | 2020-2021 |
| CHEVROLET | SUBURBAN | 2021-2022 |
| CHEVROLET | SUBURBAN 1500 | 2021-2022 |
| CHEVROLET | TAHOE | 2021-2022 |
| GMC | SIERRA 1500 | 2020-2022 |
| GMC | SIERRA 2500 | 2020-2021 |
| GMC | SIERRA 3500 | 2020-2021 |
| GMC | YUKON | 2021-2022 |
| GMC | YUKON XL | 2021-2022 |
1 Associated Document
Manufacturer Communications
Bulletin No.: 21-NA-006
Date: October, 2022
NHTSA ID Number: 10187769
Manufacturer Communication Number: 21NA006
Summary
This bulletin provides a possible location of a bad connection at the reductant fluid tanks electrical connector.
1 Associated Document
Manufacturer Communications
Bulletin No.: 21-NA-006
Date: January, 2021
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SEOCONTENT-START
Copyright 2022 General Motors LLC. All Rights Reserved. Service Bulletin Bulletin No.: 21-NA-006 Date: October, 2022 INFORMATION Subject: Diagnostic Tip to Diagnose Emission Reduction Fluid Tank Electrical Connector Inspection, Reduced Power Message, Service Emissions System, System Displayed on the Drivers Information Center (DIC) Malfunction Indicator Lamp (MIL) Illuminated – DTC P20C1, P21DD, P221C, P10D9, P10F3, P143C, P20B9, and/or P221E Brand: Model: Model Year: VIN: Engine: Transmission: from to from to Cadillac Escalade Models 2021 2022 LM2 Chevrolet Silverado 1500 2020 2021 LM2 Silverado 1500 – (LTD, RPO J21, 12th VIN Digit = 4 or less) 2022 2022 LM2 Silverado 1500 – (RPO J22, 12th VIN Digit = 5 or greater) LM2 Silverado 2500HD/ 3500HD 2020 2021 L5P Suburban 2021 2022 LM2 Tahoe 2021 2022 LM2 GMC Sierra 1500 2020 2022 LM2 Sierra 1500 – (Limited, RPO J21, 12th VIN Digit = 4 or less) 2022 2022 LM2 Sierra 1500 – (RPO J22, 12th VIN Digit = 5 or greater) LM2 Sierra 2500HD/ 3500HD 2020 2021 L5P Yukon Models 2021 2022 LM2 Page 2 October, 2022 Bulletin No.: 21-NA-006 Involved Region or Country North America, Uzbekistan, Russia, Middle East, Israel, Palestine, Chile (West), Colombia (West), Ecuador (West), Paraguay (West), Peru (West), Uruguay (West), Japan, Cadillac Korea (South Korea), Thailand (ASEAN), Australia/New Zealand Condition Some customers may comment that the MIL is illuminated and a reduced power message with a Service Emissions System message as well. Some technicians may one or more of the following DTCs set in the Engine Control Module (ECM): • P20C1: Reductant Heater 3 Control Circuit • P21DD: Reductant Tank Heater 1 Low Current • P221C: Reductant Tank Heater 2 High Current • P10D9: Reductant Heater 1 Control Circuit Shorted • P10F3: Reductant Heater 2 Control Circuit Shorted Reductant Heater 2 Control Circuit • P143C: Reductant Heater 3 Control Circuit Shorted Reductant Heater 2 Control Circuit • P20B9: Reductant Heater 1 Control Circuit • P221E: Reductant Tank Heater 3 Low Current Some technicians may also find when commanding one of the heaters on, that there is no current, 0 amps in GDS2 or unable to command the heaters on. Cause This condition may be caused by a poor connection at the Emission Reduction Fluid Tank electrical connector. Correction 5708899 Inspect the A38 – Reductant Pump and Sensor Assembly electrical connector for any signs of damage and repair as necessary. – If this condition is not found, refer to Service Information section. Note: If this condition is found on a Silverado HD or Sierra HD, check for an update to the Emissions Reductant Fluid Controller. Updating the controller will prevent this from happening again. Bulletin No.: 21-NA-006 October, 2022 Page 3 Service Information On all vehicles, replace the Emission Reduction Fluid Tank Replacement in SI. Parts Information Causal Part Description Part Number Qty X L5P: TANK, EMIS RDCN FLUID (INCLS 3,5-10) CK209,309 (43- 53) (L5P) 2020 – 2022 01 8D 5305A 85138746 1 X LM2 P/U: TANK, EMIS RDCN FLUID CK105, 107 (43) (LM2) 2020 – 2022 01 8D 5305B 84914535 1 X LM2 SUV: TANK, EMIS RDCN FLUID CK1 (06) (LM2) 2021 – 2022 01 8D 5305B 86772598 1 Warranty Information For vehicles repaired under warranty, use: Labor Operation Description Labor Time 4025130 Emission Reduction Fluid Tank Replacement Use the Published Labor Operations Time Version 2 Modified Released January 20, 2021 Revised October 10, 2022 – Fixed typo in Subject, Added Reference to A38 Pump and Sensor Assembly, and the Part number for Which Vehicle in the Correction section. GM bulletins are intended for use by professional technicians, NOT a “do-it-yourselfer”. They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information. WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
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SEOCONTENT-END
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