P2318 code meaning
Ignition Coil G Primary Control Circuit Low
Powertrain system Generic code P23xx codes Check engine light
What P2318 means
P2318 says the command wire of coil G, cylinder 7, is touching ground, so it only occurs on V8, V10 or V12 engines. GM's 2019 table for the 5.3-litre L84 truck V8 lists it as a Type B code (50 of 63 failed samples, battery above 11 V, MIL after two trips). Ford covers the series up to P2327 for its V10 and adds that the PCM cuts the injector of the affected cylinder; special service message 52455 (2024) for the 6.8 and 7.3-litre gasoline engines in Super Duty, F-53/F-59, E-Series and F-650/750 trucks names P2318 among codes the PCM may pin on the wrong cylinder, so a power balance test should confirm which cylinder really drops out. Open-circuit faults on coil G use P0357, misfire on cylinder 7 is P0307.
P2318 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P2318
- Check engine light on
- Misfire on cylinder 7
- V8 runs noticeably rough, power reduced
Common causes of P2318
- Most likelyCoil G (cylinder 7) defective
- PossibleWater or corrosion at the coil G connector
- PossibleControl wire of coil G grounded by heat or chafing damage
- Less likelyPCM cylinder mapping error on Ford 6.8/7.3 (SSM 52455)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Ignition coilCoil driverIgnition wiring
What each part of P2318 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 3 | Area: ignition system or misfire. |
| 18 | The exact fault in that area. |
What to do next
- Note P2318 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2318
What does P2318 mean?
P2318 means "Ignition Coil G Primary Control Circuit Low". P2318 says the command wire of coil G, cylinder 7, is touching ground, so it only occurs on V8, V10 or V12 engines. It is a generic code, so it means the same on every make.
Is it safe to drive with P2318?
Drive gently and only to a workshop. With P2318 the car can go into limp mode (reduced power) to protect itself.
Will P2318 fail an emissions test?
Yes, it can. P2318 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2318 to fix?
Difficulty: medium. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2318 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.