P2242: O2 Sensor Positive Current Control Circuit High (Bank 2 Sensor 1)

P2242 flags the pump-current circuit of the bank 2 front wide-band sensor as too high, usually a short to the heater feed or battery voltage, or a signal locked at its midpoint although the mixture is being changed. No manufacturer publicly documents P2242 with thresholds. Saab describes the bank 1 version P2239 for its 2.0 turbo: 1.48-1.51 V held for 1 s while closed loop enriches the mixture. Ford's 2020-2023 summary routes any short to battery on a wide-band sensor wire to P0152 instead. CARB requires fuel-control sensors to be checked for wiring faults and implausible readings. P2240 is the open circuit, P2241 the low fault, P2239 the same fault on bank 1. Since a voltage short can kill a replacement sensor, the bank 2 harness should be checked first.

Bank 2 is the side without cylinder 1, so it only exists on V or boxer engines. Sensor 1 is the oxygen sensor before the catalytic converter.

Symptoms

• Check engine light
• Bank 2 lambda value stuck near 1.0
• Replacement sensor fails again if the short remains

Most likely causes

• Bank 2 pump-current wire shorted to heater supply or battery voltage
• Internal short in the bank 2 wide-band sensor
• Damaged sensor interface in the ECM

What to check, in order

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

1. Check the wiring and connector of the sensor indicated
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Look for exhaust leaks
4. Check the signal in live data with the engine warm
5. Check the fuse and the heater resistance if the code mentions it
6. Replace the sensor if it has power and does not respond

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2242 means

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

Frequently asked questions

Can I keep driving with code P2242?

Yes, you can normally drive in moderation, but get it repaired soon: you will use more fuel and the catalytic converter can be damaged over time.

What causes code P2242?

The most common causes are: bank 2 pump-current wire shorted to heater supply or battery voltage; internal short in the bank 2 wide-band sensor; damaged sensor interface in the ECM.

Related codes

• P2240O2 Sensor Positive Current Control Circuit/Open (Bank 2 Sensor 1)
• P2241O2 Sensor Positive Current Control Circuit Low (Bank 2 Sensor 1)
• P2239O2 Sensor Positive Current Control Circuit High (Bank 1 Sensor 1)
• P0152O2 Sensor Circuit High Voltage Bank 2 Sensor 1

Sources

• law.cornell.edu: 13 CCR 1968.2
• saabwisonline.com: dtc p2237 p2239 p2243 p2251 or p2626
• fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023

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.