AutoCodes – Buick – P2627 Buick

P2627 Buick Code - HO2S Pump Current Trim Circuit Low Voltage Sensor 1

Quick Answer

The oxygen content of the exhaust is measured via the Nitrogen Oxide (NOx) sensors. Common causes include Faulty Nitrogen Oxides Sensor 1, Nitrogen Oxides Sensor 1 harness is open or shorted, Nitrogen Oxides Sensor 1 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: P2627 Buick indicates HO2S Pump Current Trim Circuit Low Voltage Sensor 1.
Common causes: Common causes include Faulty Nitrogen Oxides Sensor 1, Nitrogen Oxides Sensor 1 harness is open or shorted, Nitrogen Oxides Sensor 1 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 365

How popular is this code, among other codes? Low

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 Aug 01, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P2627 Buick Description

The oxygen content of the exhaust is measured via the Nitrogen Oxide (NOx) sensors. The NOx sensors are part of the selective catalytic reduction system, a device used to reduce NOx emission on diesel engines. There are two NOx sensors, one placed upstream of selective catalytic reduction, to measure inlet NOx concentration, and one placed downstream. They are connected with the control module via CAN and all the information is exchanged through it. Since it is a smart sensor, all the electrical monitoring is performed inside the sensor and only the results are sent to the Engine Control Module (ECM). Each NOx sensor contains a sensing cell, a pumping cell, and a heater. A sample of exhaust gas passes through a diffusion gap between the sensing cell and the pumping cell. The NOx sensor maintains a constant reference voltage across the sensing cell. An electronic circuit within the sensor controls the pump current through the pumping cell in order to maintain a constant voltage in the sensing cell. The amount of current required to maintain the reference voltage in the sensing cell is proportional to the concentration of NOx in the exhaust. The ECM varies the amount of diesel exhaust fluid (reductant) added by varying the reductant injector duty cycle in response to changes in engine exhaust NOx levels. The smart NOx sensors consist of two components, the NOx module and the NOx sensor element that are serviced as a unit. A circuit or performance condition with a NOx sensor is detected by the NOx sensor module. The smart NOx sensor module communicates the condition to the ECM over the serial data line. The ECM sets a Diagnostic Trouble Code (DTC) when a serial data message is received from the NOx sensor module.

OBDII Code P2627 Buick - HO2S Pump Current Trim Circuit Low Voltage Sensor 1 - AutoCodes.com — P2627 Buick Code - HO2S Pump Current Trim Circuit Low Voltage Sensor 1

What does this mean?

What are the Possible Causes of the DTC P2627 Buick?

Faulty Nitrogen Oxides Sensor 1
Nitrogen Oxides Sensor 1 harness is open or shorted
Nitrogen Oxides Sensor 1 circuit poor electrical connection

How to Fix the DTC P2627 Buick?

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 P2627 Buick 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 P2627 Buick code?

Need more information on how to fix the P2627 Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P2627 Buick code diagnosed by a professional: Find a repair shop in your area

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 P2627 Buick Code

1. What are common symptoms of OBDII code P2627 in a Buick?

Symptoms may include poor engine performance, rough idling, decreased fuel efficiency, and the illumination of the check engine light.

2. What causes the HO2S Pump Current Trim Circuit Low Voltage Sensor 1 code in a Buick?

The code P2627 is typically triggered by issues with the oxygen sensor (HO2S) pump current trim circuit, such as wiring faults, sensor malfunctions, or a faulty powertrain control module (PCM).

3. How serious is the P2627 code in a Buick?

While the vehicle may still be drivable with the code present, ignoring it can lead to long-term engine damage and increased emissions. It is advisable to address the issue promptly.

4. Can I drive my Buick with the P2627 code?

It is generally not recommended to drive your Buick with the P2627 code present, as it can negatively impact engine performance and fuel efficiency. It is best to have the issue diagnosed and repaired as soon as possible.

5. How do I diagnose the P2627 code in my Buick?

Diagnosing the P2627 code involves using an OBDII scanner to retrieve the code, inspecting the oxygen sensor wiring and connections, and testing the sensor's functionality using a multimeter.

6. Can I repair the P2627 code in my Buick myself?

Depending on your level of automotive knowledge, you may be able to repair the P2627 code yourself by replacing the faulty oxygen sensor, repairing wiring issues, or resetting the PCM. However, professional assistance is recommended for accurate diagnosis and repair.

7. Will resetting the PCM clear the P2627 code in my Buick?

Resetting the PCM may temporarily clear the code, but it will likely return if the underlying issue causing the P2627 code is not addressed. It is essential to diagnose and fix the root cause of the problem.

8. How much does it cost to repair the P2627 code in a Buick?

The cost of repairing the P2627 code can vary depending on the specific issue causing the code, the labor rates in your area, and whether you choose to repair it yourself or seek professional help. Costs may range from a few hundred dollars to over a thousand.

9. Can a faulty oxygen sensor cause the P2627 code in a Buick?

Yes, a faulty oxygen sensor (HO2S) can cause the P2627 code to trigger, as it plays a crucial role in monitoring the air-fuel mixture and emissions control system in the vehicle.

10. How long does it take to repair the P2627 code in a Buick?

The repair time for the P2627 code can vary depending on the exact cause of the issue and the complexity of the repair. It may take anywhere from a few hours to a full day to diagnose and fix the problem.