AutoCodes – Generic – P1622

P1622 Code - Oxygen Sensor Reference Voltage Circuit High

Quick Answer

O2 Sensor Heater Operation: For a typical Switching (4 Wire) Oxygen (O2) Sensor output signal to function the sense element must be heated to operating temperature. Common causes include Faulty Any Downstream or Upstream O2 Sensor, Any Downstream or Upstream O2 Sensor harness is open or shorted, Any Downstream or Upstream O2 Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1622 indicates Oxygen Sensor Reference Voltage Circuit High.
Common causes: Common causes include Faulty Any Downstream or Upstream O2 Sensor, Any Downstream or Upstream O2 Sensor harness is open or shorted, Any Downstream or Upstream O2 Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 44,935

How popular is this code, among other codes? Medium

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 23, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1622 Description

O2 Sensor Heater Operation: For a typical Switching (4 Wire) Oxygen (O2) Sensor output signal to function the sense element must be heated to operating temperature. A resistive heater element is incorporated within the sensor to allow for rapid heating of the sensor to reach operating temperature faster and closed-loop fuel control. The O2 Sensor Heater resistance is directly proportional to the heater temperature, meaning that as heater temperature increases, the heater resistance increases. The Powertrain Control Module (PCM) makes a calculation to determine the heater resistance and temperature. The heater resistance is calculated by measuring the battery voltage and current draw on the heater control circuit, Then the heater temperature is determined using the resistance versus temperature characteristic. The heater temperature is monitored continuously, and the heating rate is adjusted using Pulse Width Modulation (PWM) to prevent damaging the heating element. If the PCM detects a fault in the O2 Sensor heater circuitry the internal PCM driver is disabled during the current ignition cycle. The Diagnostic Trouble Code (DTC) will be set when Sensor Return circuit voltage is above approximately 3.7 volts for 9.0 seconds.

OBDII Code P1622 - Oxygen Sensor Reference Voltage Circuit High - AutoCodes.com — P1622 Code - Oxygen Sensor Reference Voltage Circuit High

What does this mean?

What are the Possible Causes of the DTC P1622?

Faulty Any Downstream or Upstream O2 Sensor
Any Downstream or Upstream O2 Sensor harness is open or shorted
Any Downstream or Upstream O2 Sensor circuit poor electrical connection

How to Fix the DTC P1622?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1622 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1622 code?

Need more information on how to fix the P1622 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1622 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1622 Audi — Instrument Panel Engine Coolant Temperature Signal Implausible Signal
P1622 BMW — Map Cooling Thermostat Control Circuit Electrical
P1622 Buick — Cylinder Select
P1622 Cadillac — Cylinder Select
P1622 Chevrolet — Cylinder Select
P1622 Dodge — Oxygen Sensor Reference Voltage Circuit High
P1622 GMC — Cylinder Select
P1622 Hyundai — A/C Control Relay Circuit Failure
P1622 Jaguar — Engine Control Module Internal Memory Performance
P1622 Mazda — Engine Control Module Incorrect Immobilizer Key Code
P1622 Nissan — Injector Adjustment Value
P1622 RAM — Oxygen Sensor Reference Voltage Circuit High
P1622 Saab — A/C Compressor Clutch Relay Low Output

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1622 Code

1. What are the common symptoms of OBDII code P1622 (Oxygen Sensor Reference Voltage Circuit High)?

- Common symptoms include poor fuel economy, rough idling, engine misfires, and the illumination of the check engine light.

2. What are the possible causes of OBDII code P1622?

- The code can be triggered by issues such as a faulty oxygen sensor, damaged wiring in the oxygen sensor circuit, or a malfunctioning engine control module (ECM).

3. How can I diagnose OBDII code P1622?

- Diagnosing this code typically involves using an OBDII scanner to retrieve the code, inspecting the oxygen sensor and its wiring for damage, and testing the reference voltage circuit for proper functioning.

4. Can I still drive my vehicle with OBDII code P1622?

- It is generally not recommended to drive the vehicle with this code as it can lead to poor engine performance and potential damage if left unaddressed.

5. How do I repair OBDII code P1622?

- Repairing this code often involves replacing a faulty oxygen sensor, repairing damaged wiring, or replacing the engine control module if necessary.

6. Are there any DIY tips for fixing OBDII code P1622?

- DIY enthusiasts can start by inspecting the oxygen sensor and its wiring for visible damage before considering replacing the sensor or seeking professional help.

7. How much does it cost to fix OBDII code P1622?

- The cost of fixing this code can vary depending on the specific issue causing it, but it may range from $100 to $500 or more, including parts and labor.

8. Can a bad oxygen sensor cause OBDII code P1622?

- Yes, a malfunctioning or damaged oxygen sensor can trigger this code by sending incorrect signals to the engine control module.

9. Will resetting the check engine light make OBDII code P1622 go away?

- Resetting the check engine light may temporarily clear the code, but it will likely reappear if the underlying issue causing it is not addressed.

10. Is it safe to ignore OBDII code P1622?

- Ignoring this code can result in decreased fuel efficiency, potential engine damage, and may lead to other more serious issues over time, so it is not recommended to ignore it.