P16AF GMC Code - Engine Controls Ignition Relay Feedback Circuit 2 Low Voltage
Quick Answer
There are 3 ignition voltage circuits supplied to the Engine Control Module (ECM). Common causes include Faulty Engine Controls Ignition Relay, Engine Controls Ignition Relay harness is open or shorted, Engine Controls Ignition 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
- P16AF GMC indicates Engine Controls Ignition Relay Feedback Circuit 2 Low Voltage.
- Common causes
- Common causes include Faulty Engine Controls Ignition Relay, Engine Controls Ignition Relay harness is open or shorted, Engine Controls Ignition 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 P16AF GMC Description
What are the Possible Causes of the DTC P16AF GMC?
- Faulty Engine Controls Ignition Relay
- Engine Controls Ignition Relay harness is open or shorted
- Engine Controls Ignition Relay circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P16AF 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 P16AF 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 P16AF GMC Code
What does the OBDII code P16AF mean on a GMC vehicle?
The P16AF code indicates a low voltage issue in the Engine Controls Ignition Relay Feedback Circuit 2, which is part of the ignition control system.
What are the symptoms of the P16AF code in a GMC?
Common symptoms include difficulty starting the engine, stalling, poor performance, and the check engine light illuminating.
What causes the P16AF code to appear?
Potential causes include a faulty ignition relay, damaged wiring or connectors in the feedback circuit, or a malfunctioning Engine Control Module (ECM).
Can I drive my GMC with the P16AF code active?
It’s not recommended to drive your vehicle with this code active, as it may lead to stalling or difficulty starting, potentially creating a safety hazard.
How do you diagnose the P16AF code?
Diagnosis typically involves checking the ignition relay, inspecting the wiring and connectors for damage or corrosion, and testing the ECM for proper functionality.
How do you fix the P16AF code on a GMC?
Repairs may include replacing the ignition relay, repairing or replacing damaged wiring or connectors, or reprogramming or replacing the ECM if necessary.
Is the P16AF code specific to GMC vehicles?
While the P16AF code is commonly associated with GMC vehicles, it may also appear on other GM models with similar systems.
How much does it cost to fix the P16AF code?
Repair costs vary, but replacing an ignition relay or repairing wiring typically costs $100–$300, while ECM replacement can cost $500–$1,500.
What tools are needed to troubleshoot the P16AF code?
Common tools include an OBDII scanner, a multimeter for checking voltage, and wiring diagrams for the ignition relay circuit.
Can a weak battery cause the P16AF code?
Yes, a weak or failing battery may cause low voltage issues, potentially triggering the P16AF code. Always check the battery health first.
Discuss the causes and fixes for P16AF GMC OBDII Code
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