P220C: NOx Sensor Supply Voltage Circuit (Bank 2 Sensor 1)

P220C is reserved for an engine with a separate exhaust path per cylinder bank, each with its own NOx sensors, and reports that the upstream sensor on bank 2 is not getting a proper supply voltage. No manufacturer documents this code publicly; the diesel pickups and trucks examined (Ford, GM, VW, Volvo/Mack) merge both banks into one SCR line and only use the bank 1 codes. By analogy with P220A, a fault would mean the supply sits outside a window like Ford's 8.5 to 16.5 V, or the supplying module reports a short. Smart sensors send their supply status over CAN, so the engine computer learns it from the sensor itself. Check fuse, relay, ground and wiring for that bank. P220D is the downstream sensor on bank 2.

Bank 2 is the side without cylinder 1, so it only exists on V or boxer engines.

Symptoms

• Malfunction indicator lamp on
• No NOx value from the bank 2 upstream sensor

Most likely causes

• Fuse, relay or ground fault in the bank 2 sensor supply
• Supply wiring to the bank 2 upstream sensor damaged
• System voltage out of range (battery or alternator)

What to check, in order

Start with the simplest. You can tick off each step.

1. Read the codes and the NOx data before and after the SCR catalyst
2. Check the sensor's connector and wiring
3. Look for exhaust leaks ahead of the sensor
4. Confirm that the AdBlue/DEF is of good quality
5. Replace the sensor only after ruling out power, ground, and leaks

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P220C means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 2: Fuel injection
• 0C: Specific fault in that system

Frequently asked questions

Can I keep driving with code P220C?

You can usually keep driving in the short term, but get it repaired soon: on many diesels, the warning eventually limits starting or engine power.

What causes code P220C?

The most common causes are: fuse, relay or ground fault in the bank 2 sensor supply; supply wiring to the bank 2 upstream sensor damaged; system voltage out of range (battery or alternator).

Related codes

• P220ANOx Sensor Supply Voltage Circuit (Bank 1 Sensor 1)
• P220BNOx Sensor Supply Voltage Circuit (Bank 1 Sensor 2)
• P220DNOx Sensor Supply Voltage Circuit (Bank 2 Sensor 2)
• P2213NOx Sensor Circuit (Bank 2)

Sources

• law.cornell.edu: 13 CCR 1968.2
• fordservicecontent.com: obd summary diesel 2023
• ni.com: NOx Sensor USB UM RevA

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.