P2634 GMC Code - Fuel Transfer Pump Relay Control Circuit High Voltage
Quick Answer
The Engine Control Module (ECM) enables the secondary fuel pump relay when the primary fuel tank is below approximately 50 liters (13.2 gallons) and will run until the primary tank is filled to approximately 70 liters (18.5 gallons) or until the secondary tank is empty. Common causes include Faulty Secondary Fuel Pump Relay, Secondary Fuel Pump Relay harness is open or shorted, Secondary Fuel Pump Relay 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
- P2634 GMC indicates Fuel Transfer Pump Relay Control Circuit High Voltage.
- Common causes
- Common causes include Faulty Secondary Fuel Pump Relay, Secondary Fuel Pump Relay harness is open or shorted, Secondary Fuel Pump Relay 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.
Code P2634 GMC Description
The control module monitors the voltage on the fuel transfer pump relay control circuit. If the control module detects an incorrect voltage on the fuel transfer pump relay control circuit, a fuel transfer pump relay control Diagnostic Trouble Code (DTC) sets.
What are the Possible Causes of the DTC P2634 GMC?
- Faulty Secondary Fuel Pump Relay
- Secondary Fuel Pump Relay harness is open or shorted
- Secondary Fuel Pump Relay circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P2634 GMC?
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 P2634 GMC 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 P2634 GMC code?
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Frequently Asked Questions about P2634 GMC Code
1. What are the common symptoms of OBDII code P2634 in a GMC related to the Fuel Transfer Pump Relay Control Circuit High Voltage?
- Common symptoms include poor engine performance, stalling, difficulty starting the vehicle, and illuminated check engine light.
2. What are the possible causes of the P2634 code in a GMC?
- The code may be triggered by issues such as a faulty fuel transfer pump relay, damaged wiring or connectors in the circuit, or a malfunctioning fuel transfer pump.
3. How can I diagnose the cause of the P2634 code in my GMC?
- A thorough inspection of the fuel transfer pump relay, wiring, and connectors is recommended. Testing the relay and checking for any visible damage to the components can help pinpoint the issue.
4. Can a DIY enthusiast repair the P2634 code in a GMC?
- Depending on the underlying cause, DIY repairs may be possible for those with automotive repair knowledge. However, complex issues may require professional diagnosis and repair.
5. Is it safe to continue driving with the P2634 code present in a GMC?
- It is not recommended to drive the vehicle with the P2634 code as it can lead to further damage and potentially unsafe driving conditions.
6. How much does it typically cost to repair the P2634 code in a GMC?
- Repair costs can vary depending on the cause of the issue, but it is advisable to budget for diagnostic fees, replacement parts, and labor costs.
7. Can the P2634 code be triggered by other underlying issues in a GMC?
- While the code specifically relates to the Fuel Transfer Pump Relay Control Circuit High Voltage, it's essential to address any related issues that may be affecting the vehicle's performance.
8. Are there any preventive measures to avoid the recurrence of the P2634 code in a GMC?
- Regular maintenance checks, including inspecting the fuel system components and electrical connections, can help prevent the reoccurrence of the P2634 code.
9. How urgent is it to address the P2634 code in a GMC?
- It is advisable to address the P2634 code promptly to avoid potential damage to the fuel system and ensure the vehicle operates safely and efficiently.
10. Can resetting the OBDII system clear the P2634 code in a GMC?
- Resetting the OBDII system may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to reappear.
Discuss the causes and fixes for P2634 GMC OBDII Code
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