Control Module U Code List
This list includes all Data Communications related U-code DTCs in alphanumeric order with descriptors for all modules. Not all DTCs listed will be applicable to all vehicles.
| DTC | DTC Descriptor |
|---|---|
| U0001 00 | High Speed CAN Bus Malfunction |
| U0001 04 | High Speed CAN Bus Malfunction Open |
| U0002 00 | High Speed CAN Bus |
| U0020 00 | Low Speed CAN Bus |
| U0028 00 | MOST Bus |
| U0029 00 | MOST Bus Performance |
| U0073 00 | Control Module Communication Bus A Off |
| U0073 01 | Control Module Communication Bus A Off Short to Battery |
| U0073 02 | Control Module Communication Bus A Off Short to Ground |
| U0073 04 | Control Module Communication Bus A Off Open |
| U0073 71 | Control Module Communication Bus A Off Invalid Data |
| U0074 00 | Control Module Communication Bus B Off |
| U0075 00 | Control Module Communication Object Detection CAN Bus Off |
| U0077 00 | Control Module Chassis Expansion Communication Bus Off |
| U0078 00 | Control Module Low Speed Communication Bus Off |
| U007A 00 | Control Module High Voltage Energy Management Communication Bus Off |
| U0100 00 | Lost Communication With Engine Control Module |
| U0100 71 | Lost Communication With Engine Control Module Invalid Data |
| U0100 72 | Lost Communication With Engine Control Module Message Counter Incorrect |
| U0100 74 | Lost Communication With Engine Control Module Bus Signal Checksum Error |
| U0101 00 | Lost Communication With Transmission Control Module |
| U0101 46 | Lost Communication With Transmission Control Module Configuration Not Programmed |
| U0101 71 | Lost Communication With Transmission Control Module Invalid Data |
| U0102 00 | Lost Communication with Transfer Case Control Module |
| U0102 46 | Lost Communication with Transfer Case Control Module Configuration Not Programmed |
| U0102 71 | Lost Communication with Transfer Case Control Module Invalid Data |
| U0104 00 | Lost Communication With Cruise Control Module |
| U0104 02 | Lost Communication With Cruise Control Module Short to Ground |
| U0104 71 | Lost Communication With Cruise Control Module Invalid Data |
| U0104 72 | Lost Communication With Cruise Control Module Message Counter Incorrect |
| U0104 74 | Lost Communication With Cruise Control Module Bus Signal Checksum Error |
| U0105 00 | Lost Communication with Fuel Injector Control Module |
| U0109 00 | Lost Communication with Fuel Pump Control Module |
| U010F 00 | Lost Communication with Air Conditioning Control Module |
| U0111 00 | Lost Communication with Battery Energy Control Module |
| U0112 00 | Lost Communication with Battery Energy Control Module |
| U0114 00 | Lost Communication with Four Wheel Drive Clutch Control Module |
| U0115 00 | Lost Communication with ECM 2 |
| U0117 00 | Lost Communication With Power Take-Off Control Module |
| U0121 00 | Lost Communication With Electronic Brake Control Module |
| U0121 03 | Lost Communication With Electronic Brake Control Module Low Voltage |
| U0121 46 | Lost Communication With Electronic Brake Control Module Configuration Not Programmed |
| U0121 71 | Lost Communication With Electronic Brake Control Module Invalid Data |
| U0121 72 | Lost Communication With Electronic Brake Control Module Message Counter Incorrect |
| U0121 74 | Lost Communication With Electronic Brake Control Module Bus Signal Checksum Error |
| U0122 00 | Lost Communication With Vehicle Stability Control Module |
| U0125 00 | Lost Communication With Multi-axis Acceleration Sensor Module |
| U0125 71 | Lost Communication With Multi-axis Acceleration Sensor Module Invalid Data |
| U0125 72 | Lost Communication With Multi-axis Acceleration Sensor Module Message Counter Incorrect |
| U0125 74 | Lost Communication With Multi-axis Acceleration Sensor Module Bus Signal Checksum Error |
| U0126 00 | Lost Communication With Steering Wheel Angle Sensor Module |
| U0126 71 | Lost Communication With Steering Wheel Angle Sensor Module Invalid Data |
| U0126 72 | Lost Communication With Steering Wheel Angle Sensor Module Message Counter Incorrect |
| U0126 74 | Lost Communication With Steering Wheel Angle Sensor Module Bus Signal Checksum Error |
| U0126 5A | Lost Communication With Steering Wheel Angle Sensor Module Not Plausible |
| U0128 00 | Lost Communication With Park Brake Control Module |
| U0128 71 | Lost Communication With Park Brake Control Module Invalid Data |
| U0128 72 | Lost Communication With Park Brake Control Module Message Counter Incorrect |
| U0128 74 | Lost Communication With Park Brake Control Module Bus Signal Checksum Error |
| U0129 00 | Lost Communication with Brake System Control Module |
| U0130 00 | Lost Communication With Electric Power Steering Control Module |
| U0130 71 | Lost Communication With Electric Power Steering Control Module Invalid Data |
| U0130 72 | Lost Communication With Electric Power Steering Control Module Message Counter Incorrect |
| U0130 74 | Lost Communication With Electric Power Steering Control Module Bus Signal Checksum Error |
| U0131 00 | Lost Communication With Power Steering Control Module |
| U0131 71 | Lost Communication With Power Steering Control Module Invalid Data |
| U0132 00 | Lost Communication With Suspension Control Module |
| U0133 00 | Lost Communication With Air Suspension Control Module |
| U0133 71 | Lost Communication With Air Suspension Control Module Invalid Data |
| U0136 00 | Lost Communication With Differential Control Module - Rear |
| U0136 71 | Lost Communication With Differential Control Module - Rear Invalid Data |
| U0137 00 | Lost Communication with Trailer Brake Control Module |
| U0139 00 | Lost Communication With Suspension Control Module |
| U0139 71 | Lost Communication With Suspension Control Module Invalid Data |
| U0140 00 | Lost Communication With Body Control Module |
| U0140 08 | Lost Communication With Body Control Module Performance - Signal Invalid |
| U0140 46 | Lost Communication With Body Control Module Configuration Not Programmed |
| U0140 71 | Lost Communication With Body Control Module Invalid Data |
| U0140 72 | Lost Communication With Body Control Module Message Counter Incorrect |
| U0140 74 | Lost Communication With Body Control Module Bus Signal Checksum Error |
| U0144 00 | Lost Communication With Body Control Module |
| U0146 00 | Lost Communication with Gateway |
| U0151 00 | Lost Communication With Inflatable Restraint Sensing and Diagnostic Module |
| U0155 00 | Lost Communication With Instrument Cluster |
| U0158 00 | Lost Communication With Head-Up Display |
| U0159 00 | Lost Communication With Parking Assist Control Module |
| U0160 00 | Lost Communication With Chime Alarm Control Module |
| U0164 00 | Lost Communication with HVAC Control Module |
| U0166 00 | Lost Communication with Auxiliary Heater Control Module |
| U0167 00 | Lost Communication with Immobilizer Control Module |
| U0168 00 | Lost Communication With Keyless Entry Control Module |
| U016B 00 | Lost Communication with Electric A/C Compressor Control Module |
| U0170 00 | Lost Communication With Passenger Presence Detection Sensor Module |
| U0181 00 | Lost Communication With Headlamp Leveling Control Module |
| U0182 00 | Lost Communication With Lighting Control Module - Front |
| U0184 00 | Lost Communication With Radio |
| U0186 00 | Lost Communication With Speaker Amplifier Module |
| U0196 00 | Lost Communication With Rear Audio Control Module |
| U0191 00 | Lost Communication With Television |
| U0193 00 | Lost Communication With Digital Radio Receiver Control Module |
| U0197 00 | Lost Communication With Telephone Control Module |
| U0198 00 | Lost Communication With Telematic Control Module |
| U0201 00 | Lost Communication With Transfer Case Control Module |
| U0203 00 | Lost Communication With Left Rear Door Switch Panel Control Module |
| U0204 00 | Lost Communication With Right Rear Door Switch Panel Control Module |
| U0207 00 | Lost Communication With Moveable Roof Control Module |
| U0208 00 | Lost Communication With Memory Seat Control Module |
| U0209 00 | Lost Communication With Front Seat Heating Control Module |
| U0210 00 | Lost Communication With Rear Seat Heating Control Module |
| U0230 00 | Lost Communication With Liftgate Control Module |
| U0232 00 | Lost Communication With Side-Object Detection Control Module - Left |
| U0233 00 | Lost Communication With Side-Object Detection Control Module - Right |
| U0236 00 | Lost Communication With Steering Column Lock Module |
| U0237 00 | Lost Communication With Multimedia Player Interface Module |
| U023A 00 | Lost Communication With Vehicle Direction Camera Control Module |
| U0248 00 | Lost Communication with Remote Accessory Module |
| U0249 00 | Lost Communication With Rear Radio Audio Control Module |
| U0250 00 | Lost Communication with Impact Classification System Module |
| U0252 00 | Lost Communication With Trailer Interface Control Module |
| U0254 00 | Lost Communication With Remote Start Module |
| U0255 00 | Lost Communication With Info Display Module |
| U0256 00 | Lost Communication With Infotainment Faceplate Control Module |
| U0257 00 | Lost Communication With Info Display Module/Infotainment Faceplate Control Module |
| U0264 00 | Lost Communication With Camera Module - Rear |
| U0265 00 | Lost Communication with Front Short Range Object Sensor 1 (left corner) |
| U0268 00 | Lost Communication with Front Short Range Object Sensor 2 (right corner) |
| U0269 00 | Lost Communication with Front Long Range Object Sensor |
| U026A 00 | Lost Communication with Camera Module - Front |
| U026B 00 | Lost Communication with Rear Short Range Object Sensor |
| U0284 00 | Lost Communication with Active Grille Air Shutter 1 Motor Module |
| U0285 00 | Lost Communication with Active Grille Air Shutter 2 Motor Module |
| U0293 00 | Lost Communication with Hybrid Powertrain Control Module |
| U0301 00 | Software Incompatibility with Engine Control Module |
| U0302 00 | Software Incompatibility with Transmission Control Module |
| U0305 00 | Software Incompatibility With Cruise Control Module |
| U0315 00 | Software Incompatibility with Electronic Brake Control Module |
| U0401 00 | Invalid Data Received from ECM |
| U0401 72 | Invalid Data Received from ECM Message Counter Incorrect |
| U0401 74 | Invalid Data Received from ECM Bus Signal Checksum Error |
| U0402 72 | Invalid Data Received From Transmission Control Module Message Counter Incorrect |
| U0402 73 | Invalid Data Received From Transmission Control Module Parity Error |
| U0402 74 | Invalid Data Received From Transmission Control Module Bus Signal Checksum Error |
| U0403 00 | Invalid Data Received From Transfer Case Control Module |
| U0405 00 | Invalid Data Received From Cruise Control Module |
| U0405 71 | Invalid Data Received From Cruise Control Module Invalid Data |
| U0405 72 | Invalid Data Received From Cruise Control Module Message Counter Incorrect |
| U0405 74 | Invalid Data Received From Cruise Control Module Bus Signal Checksum Error |
| U0415 00 | Invalid Data Received From Electronic Brake Control Module |
| U0415 72 | Invalid Data Received From Electronic Brake Control Module Message Counter Incorrect |
| U0415 74 | Invalid Data Received From Electronic Brake Control Module Bus Signal Checksum Error |
| U0416 00 | Invalid Data Received From Vehicle Dynamics Control Module |
| U0416 72 | Invalid Data Received From Vehicle Dynamics Control Module Message Counter Incorrect |
| U0416 74 | Invalid Data Received From Vehicle Dynamics Control Module Bus Signal Checksum Error |
| U0417 00 | Invalid Data Received From Park Brake Control Module |
| U0418 00 | Invalid Data Received From Brake System Control Module |
| U0418 71 | Invalid Data Received From Brake System Control Module Invalid Data |
| U0418 72 | Invalid Data Received From Brake System Control Module Message Counter Incorrect |
| U0418 74 | Invalid Data Received From Brake System Control Module Bus Signal Checksum Error |
| U0420 00 | Invalid Data Received From Power Steering Control Module |
| U0421 00 | Invalid Data Received From Suspension Control Module |
| U0422 00 | Invalid Data Received From Body Control Module |
| U0422 70 | Invalid Data Received From Body Control Module |
| U0422 72 | Invalid Data Received From Body Control Module Message Counter Incorrect |
| U0422 74 | Invalid Data Received From Body Control Module Bus Signal Checksum Error |
| U0424 00 | Invalid Data Received From HVAC Control Module |
| U0428 00 | Invalid Data Received From Steering Wheel Angle Sensor Module |
| U0431 00 | Invalid Data Received From Body Control Module "A" |
| U0432 00 | Invalid Data Received From Multi-axis Acceleration Sensor Module |
| U0432 72 | Invalid Data Received From Multi-axis Acceleration Sensor Module Message Counter Incorrect |
| U0432 74 | Invalid Data Received From Multi-axis Acceleration Sensor Module Bus Signal Checksum Error |
| U0437 71 | Invalid Data Received From Differential Control Module - Rear |
| U0438 71 | Invalid Data Received From Trailer Brake Control Module |
| U0452 00 | Invalid Data Received From Inflatable Restraint Sensing and Diagnostic Module |
| U0465 00 | Invalid Data Received From Power Take-Off Control Module |
| U0499 00 | Invalid Data Received From Telematic Control Module |
| U053B 00 | Invalid Data Received From Active Safety Control Module |
| U056B 00 | Invalid Data Received From Active Safety Control Module |
| U1193 00 | Lost Communication with Immobilizer Control Module |
| U1501 00 | LIN Bus 1 |
| U1502 00 | LIN Bus 2 |
| U150E 00 | LIN Bus 14 |
| U150F 00 | LIN Bus 15 |
| U1510 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 0 (B67 Ultrasonic Intrusion Sensor) |
| (K33 HVAC Control Module) LIN Bus 1 Lost Communication With Device 0 (A26 HVAC Control) | |
| (A11 Radio) LIN Bus 1 Lost Communication with Device 0 (A20 Radio/HVAC Control) | |
| (P16 Instrument Cluster) LIN Bus 1 Lost Communication with Device 0 (S70R Steering Wheel Controls Switch - Right) | |
| U1511 00 | (K26 Headlamp Control Module) LIN Bus 1 Lost Communication With Device 1 (E13L Headlamp Assembly-Left) |
| U1512 00 | (K26 Headlamp Control Module) LIN Bus 1 Lost Communication With Device 2 (E13R Headlamp Assembly-Right) |
| U1513 00 | (K26 Headlamp Control Module) LIN Bus 1 Lost Communication With Device 3 (E13L Headlamp Assembly-Left) |
| U1514 00 | (K26 Headlamp Control Module) LIN Bus 1 Lost Communication With Device 4 (E13R Headlamp Assembly-Right) |
| U1515 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 5 (M75 Windshield Wiper Motor) |
| U1516 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 6 (B110 Battery Sensor Module) |
| U1517 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 7 (Sunroof Sunshade Module) |
| U1518 00 | (P16 Instrument Cluster) LIN Bus 1 Lost Communication with Device 8 (P29 Head-Up Display) |
| U1519 00 | (K40 Seat Memory Control Module) LIN Bus 1 Lost Communication With Device 9 (S52 Outside Rearview Mirror Switch) |
| (K40 Seat Memory Control Module) LIN Bus 1 Lost Communication With Device 9 (K96 Mirror Control Module) | |
| U151A 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 10 (B117 Windshield Outside Moisture Sensor) |
| U151B 00 | (K9 Body Control Module) LIN Bus 1 Lost Communication With Device 11 (K61 Sunroof Control Module) |
| (K40 Seat Memory Control Module) LIN Bus 1 Lost Communication With Device 11 (S79P Window Switch - Passenger) | |
| U1520 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 0 (P25 Power Sounder Content Theft Deterrent Alarm Module) |
| U1521 00 | (K26 Headlamp Control Module) LIN Bus 2 Lost Communication With Device 1 (E13L Headlamp Assembly-Left) |
| U1522 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 2 (K65 Tire Pressure Indicator Module) |
| (K26 Headlamp Control Module) LIN Bus 2 Lost Communication With Device 2 (E13R Headlamp Assembly-Right) | |
| U1523 00 | (K26 Headlamp Control Module) LIN Bus 2 Lost Communication With Device 3 (E13L Headlamp Assembly-Left) |
| U1524 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 4 (Front Seat Heating Control Module) |
| (K26 Headlamp Control Module) LIN Bus 2 Lost Communication With Device 4 (E13R Headlamp Assembly-Right) | |
| U1526 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 6 (Rear Seat Heating Control Module) |
| U152C 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 12 (K18 Electronic Compass Module) |
| U152D 00 | (K9 Body Control Module) LIN Bus 2 Lost Communication With Device 13 (P2 Transmission Shift Lever Position Indicator) |
| U1530 00 | (K9 Body Control Module) LIN Bus 3 Lost Communication With Device 0 (M74P Window Motor - Passenger) |
| U1534 00 | (K9 Body Control Module) LIN Bus 3 Lost Communication With Device 4 (M74D Window Motor - Driver) |
| U1538 00 | (K9 Body Control Module) LIN Bus 3 Lost Communication With Device 8 (S79D Window Switch - Driver) |
| U153A 00 | (K9 Body Control Module) LIN Bus 3 Lost Communication With Device 10 (S79P Window Switch - Passenger) |
| U1540 00 | (K9 Body Control Module) LIN Bus 4 Lost Communication With Device 0 (M74RR Window Motor - Right Rear) |
| U1544 00 | (K9 Body Control Module) LIN Bus 4 Lost Communication With Device 4 (M74LR Window Motor - Left Rear) |
| U1548 00 | (K9 Body Control Module) LIN Bus 4 Lost Communication With Device 8 (S79LR Window Switch - Left Rear) |
| U154A 00 | (K9 Body Control Module) LIN Bus 4 Lost Communication With Device 10 (S79RR Window Switch - Right Rear) |
| U154B 00 | (K9 Body Control Module) LIN Bus 4 Lost Communication With Device 11 (K49 Rear Seat Control Module) |
| U15E0 00 | (A11 Radio) LIN Bus 14 Lost Communication with Device 0 |
| U15E1 00 | (A11 Radio) LIN Bus 14 Lost Communication with Device 1 |
| U15E3 00 | (A11 Radio) LIN Bus 14 Lost Communication with Device 3 |
| U15F0 00 | (K48 Infotainment Faceplate Control Module) LIN Bus 15 Lost Communication with Device 0 |
| U1793 00 | 14V Power Module Lost Communication with Hybrid Powertrain Control Module on Powertrain Expansion Communication Bus |
| U1795 00 | 14V Power Module Powertrain Expansion Communication Bus Off |
| U179A 00 | Lost Communication with Hybrid Powertrain Control Module 2 |
| U1803 00 | Lost Communication with Hybrid Powertrain Control Module 2 |
| U1806 00 | Battery Energy Control Module High Voltage Energy Management Communication Bus Off |
| U1807 00 | Battery Charger Control Module High Voltage Energy Management Communication Bus Off |
| U180A 00 | Electric A/C Compressor Control Module High Speed Communication Bus Off |
| U180B 00 | Battery Energy Control Module High Speed Communication Bus Off |
| U180C 00 | Battery Charger Control Module High Speed Communication Bus Off |
| U180D 00 | Electronic Brake Control Module Chassis Expansion Communication Bus Off |
| U1811 00 | Battery Energy Control Module Powertrain Expansion CAN Bus Off |
| U1814 01 | Powertrain Wake Up Communication Circuit Short to Battery |
| U1814 02 | Powertrain Wake Up Communication Circuit Short to Ground |
| U1814 04 | Powertrain Wake Up Communication Circuit Open |
| U1815 00 | Lost Communication with Drive Motor Control Module A on Powertrain Expansion Communication Bus |
| U1816 00 | Lost Communication with Drive Motor Control Module B on Powertrain Expansion Communication Bus |
| U1817 00 | Lost Communication with Hybrid Powertrain Control Module on Powertrain Expansion Communication Bus |
| U1818 00 | Lost Communication with Engine Control Module on Powertrain Expansion Communication Bus |
| U1821 00 | Lost Communication with 14V Power Module on Powertrain Expansion Communication Bus |
| U1826 00 | Lost Communication With Multi-Axis Acceleration Sensor Module on Bus B (Chassis Expansion Bus) |
| U1827 00 | Lost Communication With Steering Angle Sensor Module on Bus B (Chassis Expansion Bus) |
| U182A 00 | Hybrid Powertrain Control Module Lost Communication with Battery Energy Control Module on Powertrain Expansion CAN Bus |
| U182D 00 | Lost Communication with Hybrid Powertrain Control Module 2 on Powertrain Expansion Communication Bus |
| U182E 00 | Drive Motor Control Module 1 Lost Communication with Hybrid Powertrain Control Module 2 on Powertrain Expansion Communication Bus |
| U182F 00 | Drive Motor Control Module 2 Lost Communication with Hybrid Powertrain Control Module 2 on Powertrain Expansion Communication Bus |
| U1831 00 | Drive Motor Control Module A Lost Communication with Hybrid Powertrain Control Module on Powertrain Expansion CAN Bus |
| U1833 00 | Lost Communication with Electronic Brake Control Module on Chassis Expansion Communication Bus |
| U1838 00 | Lost Communication with Battery Charger Control Module on High Voltage Energy Management Communication Bus |
| U1839 00 | Auxiliary Transmission Fluid Pump Control Module Lost Communication with Engine Control Module |
| U183A 00 | Lost Communication with OnStar Module |
| U183B 00 | Auxiliary Transmission Fluid Pump Control Module Lost Communication with Transmission Control Module |
| U183C 00 | Auxiliary Transmission Fluid Pump Control Module Lost Communication with Hybrid Powertrain Control Module 2 on Powertrain Expansion Communication Bus |
| U183E 00 | Lost Communication with OnStar Module on Low Speed Communication Bus |
| U1844 00 | Battery Energy Control Module Lost Communication with Hybrid Powertrain Control Module on Powertrain Expansion Communication Bus |
| U1845 00 | Drive Motor Control Module 1 Lost Communication with Hybrid Powertrain Control Module |
| U1846 00 | Drive Motor Control Module 2 Lost Communication with Hybrid Powertrain Control Module |
| U1847 00 | Drive Motor Control Module 1 Lost Communication with Battery Energy Control Module on Powertrain Expansion CAN Bus |
| U1849 00 | Drive Motor Control Module 1 Lost Communication with Transmission Control Module |
| U184A 00 | Lost Communication with Body Control Module on Low Speed CAN Bus |
| U184B 00 | Lost Communication with Electronic Climate Control Module on Low Speed Communication Bus |
| U184C 00 | Lost Communication with Instrument Cluster on Low Speed Communication Bus |
| U184D 00 | Lost Communication with Radio on Low Speed Communication Bus |
| U184E 00 | Lost Communication with Inflatable Restraint Sensing and Diagnostic Module on Low Speed Communication Bus |
| U184F 00 | Electric A/C Compressor Control Module Lost Communication with Engine Control Module |
| U1850 00 | Drive Motor Control Module 2 Lost Communication with Transmission Control Module |
| U1858 00 | Electronic Brake Control Module Lost Communication with Hybrid Powertrain Control Module on Chassis Expansion Communication Bus |
| U185A 00 | Lost Communication with Battery Energy Control Module on High Voltage Energy Management Communication Bus |
| U185B 00 | Battery Energy Control Module Lost Communication with Hybrid Powertrain Control Module 2 on High Voltage Energy Management Communication Bus |
| U185C 00 | Battery Charger Control Module Lost Communication with Hybrid Powertrain Control Module 2 on High Voltage Energy Management Communication Bus |
| U185D 00 | Fuel Injector Control Module Lost Communication with Engine Control Module |
| U185E 00 | Fuel Injector Control Module Lost Communication with Body Control Module |
| U1860 00 | Electric A/C Compressor Control Module Lost Communication with Hybrid Powertrain Control Module 2 |
| U1861 00 | Battery Charger Control Module Lost Communication with Engine Control Module |
| U186A 00 | Electronic Brake Control Module Lost Communication with Engine Control Module |
| U186A 00 | Electronic Brake Control Module Lost Communication with Transmission Control Module |
| U1875 00 | Drive Motor Control Module 1 Lost Communication with Battery Energy Control Module |
| U1876 00 | Drive Motor Control Module 1 Lost Communication with Engine Control Module |
| U1879 00 | Drive Motor Control Module 2 Lost Communication with Engine Control Module |
| U1885 00 | Battery Energy Control Module Lost Communication with Hybrid Powertrain Control Module |
| U1886 00 | Battery Energy Control Module Lost Communication with Engine Control Module |
| U1888 00 | Hybrid Powertrain Control Module Lost Communication with Battery Energy Control Module |
| U18B9 00 | Primary High Speed CAN Bus Subnet Configuration List |
| U18BF 00 | Secondary High Speed CAN Bus Subnet Configuration List |
| U1900 00 | Lost Communication With Speech to Text Interface Module |
| U1901 00 | Lost Communication With Front Controls Multifunction Interface Module |
| U2098 00 | MOST Communication Enable Circuit |
| U2099 00 | High Speed Communication Enable Circuit |
| U2099 01 | High Speed Communication Enable Circuit Short to Battery |
| U2099 02 | High Speed Communication Enable Circuit Short to Ground |
| U2099 04 | High Speed Communication Enable Circuit Open |
| U2099 5A | High Speed Communication Enable Circuit Not Plausible |
| U209E 00 | Object Detection Control Module High Speed Communication Enable Circuit 1 |
| U209F 00 | Object Detection Control Module High Speed Communication Enable Circuit 2 |
| U2100 00 | CAN Bus Communication |
| U2101 00 | CAN Bus Maximum List of Control Modules |
| U2101 45 | CAN Bus Maximum List of Control Modules Variant Not Programmed |
| U2103 00 | Fewer Controllers On Bus Than Programmed |
| U2105 00 | Lost Communication with Engine Control Module |
| U2106 00 | Lost Communication with Transmission Control Module |
| U2107 00 | Lost Communication with Body Control Module |
| U2108 00 | Lost Communication with Electronic Brake Control Module |
| U2125 00 | Lost Communication with Telematic Unit |
| U2127 00 | Lost Communication with Front HVAC Control Module |
| U2139 00 | Lost Communication with Column Integrated Module |
| U2144 00 | Lost Communication with Distance Sensing Cruise Control Module |
| U2176 00 | Lost Communication with Power Take-Off Control Module |
| U2178 00 | Lost Communication With Trailer Interface Control Module |
| U2400 00 | Fuel Injector Control Module High Speed CAN Bus Off |
| U2401 00 | Battery Energy Control Module Dedicated Bus 1 Off |
| U2501 00 | Invalid Data Received From Hybrid Powertrain Control Module 2 |
| U2602 00 | Battery Energy Control Module Lost Communication with Hybrid Powertrain Control Module 2 |
| U2603 00 | Battery Energy Control Module Lost Communication with Hybrid Battery Interface Control Module 1 |
| U2604 00 | Battery Energy Control Module Lost Communication with Hybrid Battery Interface Control Module 2 |
| U2605 00 | Battery Energy Control Module Lost Communication with Hybrid Battery Interface Control Module 3 |
| U2606 00 | Battery Energy Control Module Lost Communication with Hybrid Battery Interface Control Module 4 |
| U2608 00 | Electric A/C Compressor Control Module Lost Communication with Hybrid Powertrain Control Module |
| U2609 00 | Battery Charger Control Module Lost Communication with Hybrid Powertrain Control Module |
| U2611 00 | Auxiliary Transmission Fluid Pump Control Module Lost Communication with Hybrid Powertrain Control Module |
| U2612 00 | Battery Charger Control Module Lost Communication with Hybrid Powertrain Control Module 2 |
Control Module U Code List
Circuit/System Verification
If this DTC is retrieved as a current DTC, replace the module that set the DTC.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for module replacement, setup, and programming
Reference Information
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
Verify DTC B1001 is not set.
- If the DTC is set, program the control module. If the DTC resets, replace the control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
Verify that DTC B101D is not set.
- If the DTC is set with symptom byte 43, program the control module that set the DTC. If the DTC resets, replace the control module that set the DTC.
- If the DTC is set with other symptom bytes, replace the control module that set the DTC.
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for control module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
Verify DTC B101E is not set.
- If the DTC is set, program the control module. If the DTC resets, replace the control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
- Verify that DTC B1325, B1330, B1370, B1380, B1424, B1440, B1441, B1517, C0800, C0899, C12E1, P0560, or P0562 is not set. If any of the DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-491140-S28645929192012073000000) .
- Verify that DTC C0550 is not set. If the DTC is set with symptom byte 39 or 43, program the control module that set the DTC. If the DTC resets, replace the control module that set the DTC. If the DTC is set with other symptom bytes, replace the control module that set the DTC.
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for module replacement, setup, and programming
Verify that DTC C056D is not set.
- If the DTC is set in a control module that can be programmed, program the control module. If the DTC resets, replace the control module that set the DTC.
- If the DTC is set in a control module that can not be programmed, replace the control module that set the DTC.
- If the DTC is set in a sensor, replace the sensor that set the DTC.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for module replacement, programming and setup
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
Verify DTC C056E is not set.
- If the DTC is set in a control module, program the control module. If the DTC resets, replace the control module that set the DTC.
- If the DTC is set in a sensor, program the sensor. If the DTC resets, replace the sensor that set the DTC.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
- Verify that DTC P0602 is not set. If the DTC P0602 is set, program the control module that set the DTC. If the DTC P0602 resets, replace the control module that set the DTC.
- Verify that DTC P0601, P0603, P0604, P0606, or P062F is not set. If any of the DTCs are set, replace the control module that set the DTC.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, programming and setup
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
With a scan tool, attempt to communicate with all control modules.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, setup, and programming.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
Action Taken When the DTCs Sets
The module uses a default value for the missing parameter.
Diagnosis of this DTC is accomplished via the symptom or an additional DTC, Refer to Symptoms - Data Communications , DTC U0100-U02FF .
- The control module suspends all message transmission.
- The control module uses default values for all parameters received on the serial data circuits.
- In the TCM, DTC U0073 will cause the transmission to go into default gears.
- In the ECM and TCM, DTC U0073 will cause the malfunction indicator lamp (MIL) to illuminate.
- If equipped with eAssist, DTC U0073 in the hybrid powertrain control module is a type B code and will cause the malfunction indicator lamp to illuminate and result in the engine operating in conventional engine mode and will maintain 14 V module operation.
- The control module inhibits the setting of all other communication DTCs.
- Refer to «Data Link References»(ref-491161-S20509971852012073000000) to determine which serial data system is used for a specific control module.
- This DTC cannot be retrieved with a current status. Diagnosis is accomplished using the symptom. Refer to «Symptoms - Data Communications»(ref-491161-S11421992392012073000000) .
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
Verify if DTC U0074 is set by the K73 Telematics Communication Interface Control Module.
- If DTC U0074 is set by the K73 Telematics Communication Interface Control Module, refer to «Scan Tool Does Not Communicate with High Speed GMLAN Device»(ref-491161-S24310616442012073000000) .
Perform the Diagnostic Repair Verification after completing the repair.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, programming and setup
Diagnosis is accomplished using the symptom. Refer to Scan Tool Does Not Communicate with Low Speed GMLAN Device .
Schematic Reference
- «Data Communication Schematics»(ref-491161-S12561536292012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000)
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
- Determine the control module that is not communicating. Refer to «Control Module U Code List»(ref-491161-S16616410652012073000000) .
- Verify that DTC U0073, U2100, U0074, U0078, U1814, U2099, B1325, B1330, B1370, B1380, B1424, B1428, B1440, B1441, B1517, C0800, C0899, C12E1, P0560, or P0562 is not set. If any of the DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-491140-S28645929192012073000000) .
- Engine running for 10 seconds.
- Ignition ON, engine OFF, verify that DTC U0100-U02FF is not set with symptom byte 00. If the DTC U0100-U02FF is set with symptom byte 00, refer to Circuit/System Testing below.
- Verify that DTC U0100-U02FF is not set with symptom byte 71 or 72. If the DTC U0100-U02FF is set with symptom byte 71 or 72 along with other DTCs set, diagnose all other codes first. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-491140-S28645929192012073000000) . If the DTC U0100-U02FF is set with symptom byte 71 or 72 and without other DTCs set, reprogram the control module. If the DTC resets, replace the control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, setup, and programming.
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
Verify the appropriate DTC is not set.
- If the DTC is set, program the control module specified by the DTC descriptor. If the DTC resets, replace the control module specified by the DTC descriptor.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
- Engine running for 10 seconds.
- Ignition ON, engine OFF, verify the DTC U0400-U05FF is not set. If the DTC U0400-U05FF is set along with other DTCs set, diagnose all other codes first. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-491140-S28645929192012073000000) . If the DTC U0400-U05FF is set without other DTCs set, program the control module specified by the DTC descriptor. If the DTC resets, replace the appropriate control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, programming and setup
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for module replacement, setup, and programming
Schematic Reference
- «Data Communication Schematics»(ref-491161-S12561536292012073000000)
- «Antilock Brake System Schematics»(ref-491195-S36202885522012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000)
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
ABS Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
- Verify the appropriate DTC is not set. If the DTC is set along with other codes, diagnose all other codes first. If no other codes are set, program the control module that set the DTC.
- With a scan tool, clear the DTCs.
- Ignition OFF, remove the scan tool, open and close the drivers door.
- Wait 60 seconds, then verify the DTC is not set. If the DTC is set, replace the appropriate control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
- Verify the appropriate DTC is not set. If the DTC is set along with other codes, diagnose all other codes first. If no other codes are set, program the control module specified by the DTC descriptor.
- With a scan tool, clear the DTCs.
- Ignition OFF, remove the scan tool, open and close the drivers door.
- Wait 60 seconds, then verify the DTC is not set. If the DTC is set, replace the appropriate control module.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for control module replacement, setup, and programming
- «Data Communication Schematics»(ref-491161-S12561536292012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000)
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool References
Control Module References for scan tool information
- Determine the control module that is not communicating. Refer to «Control Module U Code List»(ref-491161-S16616410652012073000000) .
- Verify that DTC U0073, U2100, U0074, U0078, U1814, U2099, B1325, B1330, B1370, B1380, B1424, B1428, B1440, B1441, B1517, C0800, C0899, C12E1, P0560, or P0562 is not set. If any of the DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-491140-S28645929192012073000000) .
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, programming and setup
Symptoms - Data Communications
Note. The following steps must be completed before using the symptom tables.
- Perform the «Diagnostic System Check - Vehicle»(ref-491140-S24065023222012073000000) before using the symptom tables in order to verify that all of the following are true: There are no DTCs set. The control modules can communicate via the serial data links.
- Review the system operation in order to familiarize yourself with the system functions. Refer to «Data Link Communications Description and Operation»(ref-491161-S39011673582012073000000) .
Intermittent
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information.
Perform the Diagnostic Repair Verification after completing the repair.
Schematic Reference
- «Data Communication Schematics»(ref-491161-S12561536292012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000)
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
Perform the Diagnostic Repair Verification after completing the repair.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, setup, and programming
Schematic Reference
- «Data Communication Schematics»(ref-491161-S12561536292012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000)
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Scan Tool Reference
Control Module References for scan tool information
Note. Each control module may need to be disconnected to isolate a circuit fault. Use the schematic to identify the following: Control modules the vehicle is equipped with High speed GMLAN serial data circuit terminating resistors Control module locations on the high speed GMLAN serial data circuits Each control module's high speed GMLAN serial data circuit terminals
- Attempt to communicate with all control modules on the high speed GMLAN serial data circuit Refer to «Data Link References»(ref-491161-S20509971852012073000000) . Communications should not be available with two or more control modules on the high speed GMLAN serial data circuit. If only one control module is not communicating, diagnose that control module only. Refer to «DTC U0100-U02FF»(ref-491161-S42425685932012073000000) .
- Disconnect the scan tool from the X84 data link connector (DLC). The following tests will be done at the DLC connector.
- Ignition OFF and all vehicle systems OFF, all keys at least 3 meters away from vehicle, all access doors closed. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, test for less than 4.5 V between the serial data circuits listed below and ground: Terminal 6 Terminal 14 If greater than the specified range, test the serial data circuit for a short to voltage. Refer to Testing the Serial Data Circuits for a Short to Voltage below.
- Ignition OFF and all vehicle systems OFF, all keys at least 3 meters away from vehicle, all access doors closed. It may take up to 2 minutes for all vehicle systems to power down. Test for greater than 100 ohms between the serial data circuits listed below and ground: Terminal 6 Terminal 14 If less than the specified range, test the serial data circuit for a short to ground. Refer to Testing the Serial Data Circuits for a Short to ground below.
- Test for 50-70 ohms between the serial data circuits terminal 6 and terminal 14. If less than 35 ohms, test for a short between the serial data circuits. Refer to Testing the Serial Data Circuits for a Short between the Circuits below. If 35-50 ohms there may be a third terminating resistor between the serial data circuits. This can happen if the incorrect control module is installed. Some control modules are available with and without the terminating resistors installed to reduce the need of terminating resistors in the wiring harness. If greater than 70 ohms but less than infinite, test the serial data circuit for an open/high resistance. Refer to Testing the Serial Data Circuits for an Open/High Resistance below. If infinite, test the serial data circuits between the DLC and the first connection to the serial data circuit for an open/high resistance.
Perform the Diagnostic Repair Verification after completing the repair.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for control module replacement, setup, and programming
Schematic Reference
Data Communication Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
- «Circuit Testing»(ref-491170-S01761107082012073000000)
- «Connector Repairs»(ref-491170-S29468502572012073000000)
- «Testing for Intermittent Conditions and Poor Connections»(ref-491170-S23088445062012073000000)
- «Wiring Repairs»(ref-491170-S24000289392012073000000)
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- «GMLAN Wiring Repairs»(ref-491170-S26457615942012073000000)
- «Control Module References»(ref-491163-S28884786072012073000000) for module replacement, programming and setup
Data Link References
This table identifies which serial data link that a particular module uses for in-vehicle data transmission. Some modules may use more than one data link to communicate. Some modules may have multiple communication circuits passing through them without actively communicating on that data link. This table is used to assist in correcting a communication malfunction. Not all modules listed will be applicable to all vehicles. Refer to the schematics to determine which modules apply. For the description and operation of these serial data communication circuits refer to Data Link Communications Description and Operation .
| Control Module | Data Link Type | Diagnostic Procedure |
|---|---|---|
| Schematic Reference: Data Communication Schematics | ||
| Body Control Module | High Speed GMLAN Low Speed GMLAN Local Interconnect Network (LIN) | Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF |
| Electronic Brake Control Module | High Speed GMLAN Chassis High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device |
| Engine Control Module | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device |
| Fuel Pump Control Module | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device |
| HVAC Control Module | Low Speed GMLAN Local Interconnect Network (LIN) | Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF |
| Inflatable Restraint Sensing and Diagnostic Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Info Display Module | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Instrument Cluster | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Liftgate Control Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Mirror Control Module - Left | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Multi-axis Acceleration Sensor | Chassis High Speed GMLAN | Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device |
| Multimedia Player Interface Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Parking Assist Control Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Passenger Presence Detection Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Power Steering Control Module | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device |
| Radio | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Radio/HVAC Controls | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Rear Differential Clutch Control Module | High Speed GMLAN Chassis High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device |
| Seat Heating Control Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Seat Memory Control Module | Low Speed GMLAN Local Interconnect Network (LIN) | Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF |
| Steering Wheel Angle Sensor | Chassis High Speed GMLAN | Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device |
| Sunroof Motor | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Telematics Communication Interface Control Module | High Speed GMLAN Low Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Low Speed GMLAN Device |
| Transmission Control Module | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device |
| Transmission Shift Lever Position Indicator | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Window Switch - Driver | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Window Switch - Left Rear | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Window Switch - Passenger | Local Interconnect Network (LIN) | DTC U1500-U15BF |
| Window Switch - Right Rear | Local Interconnect Network (LIN) | DTC U1500-U15BF |
Data Link References
Scheme 13
| Callout | Component Name |
|---|---|
| Preliminary Procedure Remove the drivers side insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side (Equinox) , Instrument Panel Insulator Panel Replacement - Left Side (Terrain) Remove the driver knee bolster reinforcement. Refer to Driver Knee Bolster Reinforcement Replacement (Equinox) , Driver Knee Bolster Reinforcement Replacement (Terrain) | |
| 1 | Body Control Module Procedure Disconnect the electrical connectors. Depress the tab on the bracket and slide the module forward. Reprogram the module if replaced. Refer to Control Module References . |
Body Control Module Replacement
Power Mode Master
This vehicle body control module (BCM) functions as the power mode master (PMM). The ignition switch is a low current switch with multiple discrete ignition switch signals to the PMM for determining the power mode that will be sent over the serial data circuits to the other modules that need this information; the PMM will activate relays and other direct outputs of the PMM as needed. Refer to Power Mode Description and Operation for a complete description of power mode functions.
Gateway
The body control module (BCM) in this vehicle functions as a gateway or translator. The purpose of the gateway is to translate serial data messages between the GMLAN high speed bus and the GMLAN low speed bus for communication between the various modules. The gateway will interact with each network according to that network's transmission protocol.
All communication between the BCM and a scan tool is on the high speed GMLAN serial data circuits. A lost communication DTC typically is set in modules other than the module with a communication failure.
Body Control
The various body control module (BCM) input and output circuits are illustrated in the corresponding functional areas on the BCM electrical schematics. Refer to the Body Control System Schematics for more detailed information.
Data Link Connector (DLC)
The data link connector (DLC) is a standardized 16-cavity connector. Connector design and location is dictated by an industry wide standard, and is required to provide the following
- Pin 1 Low speed GMLAN communications terminal
- Pin 2 Class 2 communications terminal
- Pin 3 Mid speed GMLAN serial bus (+) terminal
- Pin 4 Scan tool power ground terminal
- Pin 5 Common signal ground terminal
- Pin 6 High speed GMLAN serial data bus (+) terminal
- Pin 7 Keyword communications terminal
- Pin 11 Mid speed GMLAN serial bus (-) terminal
- Pin 12 Chassis high speed GMLAN serial bus (+) terminal
- Pin 13 Chassis high speed GMLAN serial bus (-) terminal
- Pin 14 High speed GMLAN serial data bus (-) terminal
- Pin 16 Scan tool power, battery positive voltage terminal
Serial Data Reference
The scan tool communicates over the various buses on the vehicle. When a scan tool is installed on a vehicle, the scan tool will try to communicate with every control module that could be optioned into the vehicle. If an option is not installed on the vehicle, the scan tool will display No Comm for that optional control module. In order to avert misdiagnoses of No Communication with a specific control module, refer to Data Link References for a list of control modules, the buses they communicate with, and the RPO codes for a specific control module.