Ignition Coil "F" Primary Control Circuit Low
P2315 indicates the PCM detected a low voltage condition in the primary control circuit for ignition coil F. This means the ignition coil driver circuit is not receiving proper voltage signals, preventing the coil from generating spark for that cylinder's fuel injector operation may be disabled.
What You Might Notice
- Engine misfire on cylinder F
- Diminished engine performance and power loss
- Reduced fuel efficiency
- Check engine light illumination
- Rough idle or hesitation during acceleration
Most Common Causes
- 1
Faulty ignition coil F
The coil pack for cylinder F may have failed internally, preventing proper primary circuit voltage transmission to the PCM.
- 2
Damaged wiring or connectors
Corroded, loose, or broken wires and connectors in the ignition coil F circuit reduce voltage signal delivery to the control module.
- 3
PCM or driver module failure
The powertrain control module or ignition control driver circuit may be malfunctioning and unable to properly command the ignition coil.
- 4
Low system voltage
A weak battery or charging system failure may reduce overall system voltage below the threshold needed for proper coil operation.
How to Diagnose It
- 1
Check Faulty ignition coil F — The coil pack for cylinder F may have failed internally, preventing proper primary circuit voltage transmission to the PCM.
- 2
Check Damaged wiring or connectors — Corroded, loose, or broken wires and connectors in the ignition coil F circuit reduce voltage signal delivery to the control module.
- 3
Check PCM or driver module failure — The powertrain control module or ignition control driver circuit may be malfunctioning and unable to properly command the ignition coil.
- 4
Check Low system voltage — A weak battery or charging system failure may reduce overall system voltage below the threshold needed for proper coil operation.
How to Fix It
- 1
Test and replace ignition coil F
Use a multimeter to test the coil's primary and secondary resistance. If out of specification or coil fails testing, replace with a new ignition coil pack for cylinder F.
- 2
Inspect and repair wiring and connectors
Check the ignition coil connector and wiring harness for corrosion, loose pins, or damage. Clean connectors with dielectric grease and repair or replace damaged wiring as needed.
- 3
Test battery and charging system
Verify battery voltage is above 12.6V at rest and alternator output is 13.5-14.5V at idle. Replace battery or repair alternator if voltage is low.
- 4
Have PCM diagnosed by specialist
If coil, wiring, and voltage are all normal, the PCM or ignition driver module may need professional diagnosis or reprogramming by a dealer.
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