GMC fault codes
Coverage shown is GM data: 17,703 codes · 2,212 vehicle records · 180 ECU records · 10,756 live-data parameters.
GMC shares fault-code data with GM. Data may not cover GMC-specific systems.
Codes 17,703
| Code | Description | Brands | System |
|---|---|---|---|
| P21B0 | Reductant level sensor 'C' circuit high | 11 | Powertrain |
| P21C5 | Reductant level sensor 'A' stuck | 14 | Powertrain |
| P21C6 | Reductant level sensor 'B' stuck | 11 | Powertrain |
| P21CB | Reductant control module supply voltage low | 16 | Powertrain |
| P21CC | Reductant control module supply voltage high | 18 | Powertrain |
| P21CF | Cylinder 1 injector 'B' circuit/open | 19 | Powertrain |
| P21D0 | Cylinder 2 injector 'B' circuit/open | 19 | Powertrain |
| P21D1 | Cylinder 3 injector 'B' circuit/open | 18 | Powertrain |
| P21D2 | Cylinder 4 injector 'B' circuit/open | 15 | Powertrain |
| P21D3 | Cylinder 5 injector 'B' circuit/open | 14 | Powertrain |
| P21D4 | Cylinder 6 injector 'B' circuit/open | 14 | Powertrain |
| P21D5 | Cylinder 7 injector 'B' circuit/open | 12 | Powertrain |
| P21D6 | Cylinder 8 injector 'B' circuit/open | 12 | Powertrain |
| P21DB | Compressed Natural Gas (CNG) Injector Line Voltage Low (Cylinder 1) | 19 | Powertrain |
| P21DC | Compressed Natural Gas (CNG) Injector Line Voltage High (Cylinder 1) | 20 | Powertrain |
| P21DD | Reductant heater 'A' current too low | 12 | Powertrain |
| P21DE | Compressed Natural Gas (CNG) Injector Line Voltage Low (Cylinder 2) | 19 | Powertrain |
| P21DF | Compressed Natural Gas (CNG) Injector Line Voltage High (Cylinder 2) | 20 | Powertrain |
| P21E0 | Compressed Natural Gas (CNG) Injector Line Voltage Low (Cylinder 3) | 19 | Powertrain |
| P21E1 | Compressed Natural Gas (CNG) Injector Line Voltage High (Cylinder 3) | 19 | Powertrain |
| P21E2 | Compressed Natural Gas (CNG) Injector Line Voltage Low (Cylinder 4) | 16 | Powertrain |
| P21E3 | Compressed Natural Gas (CNG) Injector Line Voltage High (Cylinder 4) | 16 | Powertrain |
| P21E4 | Cylinder 5 injector 'B' circuit low | 12 | Powertrain |
| P21E5 | Cylinder 5 injector 'B' circuit high | 12 | Powertrain |
| P21E6 | Cylinder 6 injector 'B' circuit low | 12 | Powertrain |
| P21E7 | Cylinder 6 injector 'B' circuit high | 12 | Powertrain |
| P21E8 | Cylinder 7 injector 'B' circuit low | 12 | Powertrain |
| P21E9 | Cylinder 7 injector 'B' circuit high | 12 | Powertrain |
| P21EA | Cylinder 8 injector 'B' circuit low | 12 | Powertrain |
| P21EB | Cylinder 8 injector 'B' circuit high | 12 | Powertrain |
| P2200 | NOx Sensor Circuit Bank 1 | 33 | Powertrain |
| P2201 | Input voltage is higher than 360 volts | 30 | Powertrain |
| P2202 | Output voltage is less than 250 volts | 29 | Powertrain |
| P2203 | NOx Sensor Circuit High (Bank 1 Sensor 1) | 31 | Powertrain |
| P2204 | DC/DC converter internal temperature is higher than 90°C | 27 | Powertrain |
| P2205 | NOx Sensor Heater Control Circuit/Open (Bank 1 Sensor 1) | 27 | Powertrain |
| P2206 | NOx Sensor Heater Control Circuit Low Bank 1 | 27 | Powertrain |
| P2207 | NOx Sensor Heater Control Circuit High (Bank 1 Sensor 1) | 27 | Powertrain |
| P2208 | NOx Sensor Heater Sense Circuit (Bank 1 Sensor 1) | 28 | Powertrain |
| P2209 | NOx Sensor Heater Sense Circuit Range/Performance (Bank 1 Sensor 1) | 28 | Powertrain |
| P220A | NOx Sensor Supply Voltage Circuit (Bank 1 Sensor 1) | 22 | Powertrain |
| P220B | NOx Sensor Supply Voltage Circuit (Bank 1 Sensor 2) | 20 | Powertrain |
| P2210 | NOx Sensor Heater Sense Circuit Low (Bank 1 Sensor 1) | 28 | Powertrain |
| P2211 | NOx Sensor Heater Sense Circuit High Bank 1 | 28 | Powertrain |
| P2212 | NOx Sensor Heater Sense Circuit Intermittent Bank 1 | 25 | Powertrain |
| P2213 | NOx sensor circuit bank 2 | 26 | Powertrain |
| P2214 | NOx sensor circuit range/performance bank 2 | 27 | Powertrain |
| P2215 | NOx sensor circuit low bank 2 | 26 | Powertrain |
| P2216 | NOx sensor circuit high bank 2 | 26 | Powertrain |
| P2217 | NOx sensor circuit intermittent bank 2 | 25 | Powertrain |
Some brand data is extracted from diagnostic files and may contain manufacturer-specific wording. General SAE J2012 descriptions are used where available.