P135B on 2018-2020 Chevrolet Traverse (L, LS, LT, RS, Premier, High Country) — Ignition Coil Supply Voltage Circuit Bank 2
1 vehicles · 1 makes · $150-$900 repair
Most Reported On
P135B is an OBD-II diagnostic trouble code meaning “Ignition Coil Supply Voltage Circuit Bank 2.” Manufacturer-specific (General Motors — Buick, Cadillac, Chevrolet, GMC). Each cylinder has its own ignition coil, and the engine control module monitors the battery-voltage feed running from the fuse to the bank 2 coils. This code sets when the ECM detects less than about 2.5 volts on that supply circuit. With no voltage to the coils, the cylinders on that bank cannot fire, so the engine misfires badly, runs rough, loses power, and may not start. Note that BMW and MINI use P135B for an implausible knock sensor 2 signal instead, so confirm the definition against your make. This code is most commonly reported on 2018-2020 Chevrolet Traverse (L, LS, LT, RS, Premier, High Country), with repair costs ranging from $150 to $900.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
P135B does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.
FAQ
What does P135B mean?
P135B stands for "Ignition Coil Supply Voltage Circuit Bank 2." Manufacturer-specific (General Motors — Buick, Cadillac, Chevrolet, GMC). Each cylinder has its own ignition coil, and the engine control module monitors the battery-voltage feed running from the fuse to the bank 2 coils. This code sets when the ECM detects less than about 2.5 volts on that supply circuit. With no voltage to the coils, the cylinders on that bank cannot fire, so the engine misfires badly, runs rough, loses power, and may not start. Note that BMW and MINI use P135B for an implausible knock sensor 2 signal instead, so confirm the definition against your make.
What are the most common causes of P135B?
The most common causes of P135B are: Blown ignition coil fuse for bank 2, Short to ground in the ignition voltage supply circuit, Open or high resistance in the coil power feed or a corroded connector, Failed ignition coil on bank 2 shorting the supply, Damaged or chafed engine harness near the valve cover, Faulty engine control module (rare — verify circuits first). The specific cause varies by vehicle.
How much does it cost to fix P135B?
Repair costs for P135B range from $150 to $900, depending on the vehicle and root cause.
Which vehicles are affected by P135B?
Au7o has documented P135B across 1 vehicle models from 1 manufacturers: Chevrolet.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.