P0628 Cadillac Code - Fuel Pump Speed Output Circuit Low Voltage
Quick Answer
The P0628 code for Cadillac vehicles indicates that there is a low voltage condition in the fuel pump speed output circuit. Common causes include Faulty fuel pump, Damaged wiring or connectors in the fuel pump speed output circuit, Issues with the fuel pump relay. 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
- P0628 Cadillac indicates Fuel Pump Speed Output Circuit Low Voltage.
- Common causes
- Common causes include Faulty fuel pump, Damaged wiring or connectors in the fuel pump speed output circuit, Issues with the fuel pump relay.
- 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 P0628 Cadillac Description
The P0628 code for Cadillac vehicles indicates that there is a low voltage condition in the fuel pump speed output circuit. This means that the powertrain control module (PCM) has detected a voltage level that is lower than the specified range for the fuel pump speed signal. The fuel pump speed output circuit is responsible for monitoring and controlling the speed of the fuel pump, which is crucial for delivering the correct amount of fuel to the engine. A low voltage in this circuit can lead to issues with fuel delivery, potentially causing performance problems and affecting overall engine function.
Common Causes of P0628 Cadillac
- Faulty fuel pump
- Damaged wiring or connectors in the fuel pump speed output circuit
- Issues with the fuel pump relay
- PCM malfunction or software issues
- Electrical problems such as a short or open circuit
Symptoms of P0628 Cadillac
- Engine misfires or hesitation during acceleration
- Difficulty starting the vehicle
- Reduced fuel efficiency
- Illumination of the check engine light
- Engine stalling or shutting off unexpectedly
How to Fix P0628 Cadillac
- Begin by diagnosing the root cause of the issue using a scan tool to read the fault codes and perform a thorough inspection of the fuel pump speed output circuit.
- Test the fuel pump operation and check for proper voltage levels at the fuel pump connector.
- Inspect the wiring harness and connectors for any signs of damage, corrosion, or loose connections. Repair or replace as needed.
- Test the fuel pump relay and replace if faulty.
- Clear the fault codes and perform a test drive to ensure that the issue has been resolved.
Cost to Fix P0628 Cadillac
The cost of repairing a P0628 code in a Cadillac can vary depending on the specific cause of the issue and the labor rates in your area. On average, you can expect to pay anywhere from $200 to $500 for parts and labor. Keep in mind that diagnostic time and labor rates at auto repair shops can fluctuate, so it's best to get a personalized estimate from a trusted mechanic.
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Frequently Asked Questions about P0628 Cadillac Code
1. What does the OBDII code P0628 mean for a Cadillac?
Code P0628 indicates a Fuel Pump Speed Output Circuit Low Voltage, meaning the ECM is detecting a low voltage condition in the fuel pump control circuit.
2. What are the common symptoms of code P0628 in a Cadillac?
Symptoms may include difficulty starting the engine, reduced fuel efficiency, engine stalling, or a complete failure to start.
3. What causes code P0628 to appear in a Cadillac?
Common causes include a faulty fuel pump relay, damaged wiring or connectors in the fuel pump circuit, a failing fuel pump, or a malfunctioning ECM.
4. How do you diagnose code P0628 on a Cadillac?
Diagnosis typically involves inspecting the fuel pump relay, checking wiring and connectors for damage or corrosion, and testing the fuel pump's voltage and resistance.
5. Can a faulty fuel pump trigger code P0628 in a Cadillac?
Yes, a failing or damaged fuel pump can cause low voltage in the circuit, leading to the P0628 code.
6. Is it safe to drive a Cadillac with code P0628?
Driving with code P0628 is not recommended as it can lead to engine stalling or failure to start, potentially leaving you stranded.
7. How can I fix code P0628 on a Cadillac?
Repairs may include replacing the fuel pump relay, repairing or replacing damaged wiring, cleaning corroded connectors, or replacing the fuel pump.
8. Can the ECM cause code P0628 on a Cadillac?
Yes, a malfunctioning ECM can incorrectly detect or cause low voltage in the fuel pump circuit, leading to the P0628 code.
9. How much does it cost to repair code P0628 on a Cadillac?
Repair costs vary depending on the issue but can range from $100 for wiring repairs to over $500 if the fuel pump needs replacement.
10. Will clearing the code P0628 solve the issue in a Cadillac?
Clearing the code may temporarily remove it, but the underlying problem must be addressed to prevent the code from returning.
Discuss the causes and fixes for P0628 Cadillac OBDII Code
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07 Cadillac sts 3.6 crank but don't start,was starting fine.I turned off to run in a place and tried to restart too leave,the crank no start beganed.Since I replaced the fuel pump,crank sensor and purge valve but still crank no start.the p0628 code is al I have to go on.
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Unfortunately, I haven't had that problem before, but I searched a national database of repairs for the same model and year. A couple of technicians had the same code fixed the problem by cleaning the throttle body. If the problem persists, then you should replace the fuel pump relay.
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If there is an issue with the Fuel Pump Module, Fuel Pump, or Relay, the engine will attempt to crank but will not successfully start.
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