2012 Ford F-150 EcoBoost Codes P2309 & P2306, Rough Idle, No Power

Hi everyone,

I’m having issues with my 2012 Ford F-150 EcoBoost. The truck has a rough idle and no power, and I’m getting codes P2309 and P2306. Here’s what I’ve done so far:

  • Replaced the spark plugs.
  • Replaced the ignition coil packs.

Despite this, the codes persist, and the engine is still running rough with no improvement in power.

Fault Code Details:

  • P2306: Ignition Coil ‘C’ Primary Control Circuit Low.
  • P2309: Ignition Coil ‘D’ Primary Control Circuit Low.

Possible Causes I’ve Considered:

  1. Wiring Issues: Could there be damaged or corroded wiring in the ignition circuit?
  2. Connector Problems: Maybe the connectors to the ignition coils are loose or damaged?
  3. ECM Issues: Is it possible the ECM isn’t providing proper input to the ignition coil’s primary circuit?

I’d appreciate any advice or tips on how to troubleshoot further. What’s the best way to test the wiring or connectors, and should I be looking at the ECM at this point? Thanks in advance!

It sounds like a wiring or connector issue. Start by checking the wiring harness for any damage or corrosion. Pay close attention to the wires leading to coils C and D.

FordWorrior said:
It sounds like a wiring or connector issue. Start by checking the wiring harness for any damage or corrosion. Pay close attention to the wires leading to coils C and D.

Good call. A multimeter can help test for continuity in the wires. If there’s a break, you’ll need to repair or replace the affected section of the harness.

If you’ve ruled out wiring, it’s worth testing the connectors to the ignition coils. Sometimes, a loose or damaged connector can cause these issues. Look for signs of corrosion or bent pins.

Mickey said:
If you’ve ruled out wiring, it’s worth testing the connectors to the ignition coils. Sometimes, a loose or damaged connector can cause these issues. Look for signs of corrosion or bent pins.

I had a similar issue on my F-150. Cleaning the connectors with electrical contact cleaner fixed the problem for me.

The ECM is a possibility, but it’s less likely than a wiring or connector issue. If you suspect the ECM, have it tested or reflashed before replacing it. It’s expensive, so make sure it’s the culprit first.

Have you checked for a blown fuse? Sometimes, issues with the ignition circuit can be as simple as a fuse. Double-check your fuse box for anything related to the coils.

Arden said:
Have you checked for a blown fuse? Sometimes, issues with the ignition circuit can be as simple as a fuse. Double-check your fuse box for anything related to the coils.

Good point! I once had a similar issue, and it turned out to be a blown fuse in the PCM power circuit.

If all else fails, check for any TSBs (Technical Service Bulletins) related to the ignition system for your model year. Sometimes, these codes are linked to known issues that Ford has addressed.