P1A78 GMC Code - Starter/Generator Control Module Coolant Temperature Sensor 3 Performance
Quick Answer
The Starter/Generator Control Module (SGCM) monitors its internal fluid temperature sensors to control the SGCM coolant pump and SGCM cooling fan. Common causes include Faulty Starter/Generator Control Module (SGCM), Starter/Generator Control Module (SGCM) harness is open or shorted, Starter/Generator Control Module (SGCM) 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
- P1A78 GMC indicates Starter/Generator Control Module Coolant Temperature Sensor 3 Performance.
- Common causes
- Common causes include Faulty Starter/Generator Control Module (SGCM), Starter/Generator Control Module (SGCM) harness is open or shorted, Starter/Generator Control Module (SGCM) 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 P1A78 GMC Description
What are the Possible Causes of the DTC P1A78 GMC?
- Faulty Starter/Generator Control Module (SGCM)
- Starter/Generator Control Module (SGCM) harness is open or shorted
- Starter/Generator Control Module (SGCM) circuit poor electrical connection
How to Fix the DTC P1A78 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 P1A78 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.
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Frequently Asked Questions about P1A78 GMC Code
1. What does the OBDII code P1A78 mean for a GMC vehicle?
Code P1A78 indicates a performance issue with the Starter/Generator Control Module Coolant Temperature Sensor 3, which monitors coolant temperature to ensure proper operation of the hybrid or electric system.
2. What are the common symptoms of code P1A78 in a GMC?
Symptoms may include reduced hybrid/electric performance, warning lights on the dashboard, or an overheating starter/generator control module.
3. What causes the P1A78 code to appear in a GMC?
Possible causes include a faulty coolant temperature sensor, wiring issues, connector problems, or a malfunction in the Starter/Generator Control Module.
4. Can I drive my GMC with a P1A78 code?
It’s not recommended to drive for extended periods with this code, as it may lead to overheating or reduced system efficiency, potentially causing further damage.
5. How is the P1A78 code diagnosed in a GMC?
Technicians typically use a scan tool to verify the code, inspect the coolant temperature sensor and related wiring, and perform tests to determine sensor functionality and connectivity.
6. How do I fix the P1A78 code on my GMC?
Repairs may include replacing the coolant temperature sensor, repairing damaged wiring or connectors, or addressing issues with the Starter/Generator Control Module.
7. How much does it cost to fix a P1A78 code in a GMC?
Repair costs can vary depending on the extent of the issue but typically range from $150 to $500 for parts and labor.
8. Can a low coolant level trigger the P1A78 code?
Yes, low coolant levels can affect the sensor’s readings and contribute to this code, so it’s important to check and maintain proper coolant levels.
9. Does the P1A78 code affect fuel efficiency in a GMC?
Yes, the code can lead to reduced hybrid system efficiency, potentially impacting overall fuel economy.
10. Is the Starter/Generator Control Module always the issue with code P1A78?
No, the module may not always be the issue. Faulty sensors, wiring, or connectors are more common causes for this code.
Discuss the causes and fixes for P1A78 GMC OBDII Code
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