Ignition Coil F Primary Control Circuit Low

[CCXVI]

Getting that fault, swapped coils and it didn't move. Checked voltage at the coil plug and its 14. I just replaced injector 1 because it was stuck, now I'm not getting the black smoke but I'm still misfiring just on a different cylinder.

So verify, ignition coil F is on cylinder 6 right? And if I've swapped coils and I'm getting voltage, what else could it be?

 

[SHOdded]

Yes, cylinder 6 - possibly pulled a pin in the loom ...

P0356 Ignition Coil F Primary/Secondary Circuit Malfunction

https://www.obd-codes.com/p0356

• ignition coils (12029)
• ignition coil harness
• ignition coils relay
• powertrain control module (PCM) (12A650)

JF2 CHECK THE FUNCTIONALITY OF THE SUSPECT COIL DRIVER CIRCUIT

• Ignition OFF.
• Suspect coil connector disconnected.
• Remove the fuel pump fuse to disable the fuel pump.
• Connect the Deluxe Noid Lite and Signal Test Light Set AST7898 or equivalent between the IGN START/RUN and suspect coil driver, harness side.
• Observe the noid light while cranking the engine.

This helps determine whether the coil driver in the PCM is at issue or whether to check the coil next.

These pinouts are for a 2011, may be different for 2013+
COP
Flex GTDI 3.5L, MKS 3.5L, MKT 3.5L, Taurus GTDI 3.5L C 1
Pin 1 COP
Pin 3 IGN START/RUN

PCM
Flex GTDI 3.5L, MKS 3.5L, MKT 3.5L, Taurus GTDI 3.5L
190-PIN

E33 COP6
E50 COP5
E54 COP4
E55 COP3
E56 COP2
E66 COP1

 

[CCXVI]

Alright, I'll order one of those light sets and see what I can find.

 

[Johnbigdog]

Alright, I'll order one of those light sets and see what I can find.

Are you talking about a noid light? A high impedance test light will do the same thing.

 

[CCXVI]

Are you talking about a noid light? A high impedance test light will do the same thing.

The noid light set will be here tomorrow. I'd rather order the right thing than something I can make work.

 

[CCXVI]

Yes, cylinder 6 - possibly pulled a pin in the loom ...

P0356 Ignition Coil F Primary/Secondary Circuit Malfunction

https://www.obd-codes.com/p0356

• ignition coils (12029)
• ignition coil harness
• ignition coils relay
• powertrain control module (PCM) (12A650)

JF2 CHECK THE FUNCTIONALITY OF THE SUSPECT COIL DRIVER CIRCUIT

• Ignition OFF.
• Suspect coil connector disconnected.
• Remove the fuel pump fuse to disable the fuel pump.
• Connect the Deluxe Noid Lite and Signal Test Light Set AST7898 or equivalent between the IGN START/RUN and suspect coil driver, harness side.
• Observe the noid light while cranking the engine.

This helps determine whether the coil driver in the PCM is at issue or whether to check the coil next.

These pinouts are for a 2011, may be different for 2013+View attachment 10639
COP
Flex GTDI 3.5L, MKS 3.5L, MKT 3.5L, Taurus GTDI 3.5L C 1
Pin 1 COP
Pin 3 IGN START/RUN

PCM
Flex GTDI 3.5L, MKS 3.5L, MKT 3.5L, Taurus GTDI 3.5L
190-PIN

E33 COP6
E50 COP5
E54 COP4
E55 COP3
E56 COP2
E66 COP1

Checked this, light came on while it was running. But changing the coil didn't move the problem, the coil that was originally on cyl 6 is happily running cyl 4 now, and I'm still getting the fault for cyl 6 when I clear them and wait for it to come back (which is usually less than a minute)

 

[SHOdded]

The manual goes on to pinpoint test Z, if the noid light was blinking consistently. Meaning that whatever is happening is intermittent and should be diagnosed that way.

However, I would proceed to check the coil driver in the PCM anyway. Also check the connectors at the PCM for water intrusion, rust, grime, etc. That can cause some funny things to happen.

JF4 CHECK THE IGNITION START/RUN SUPPLY TO THE SUSPECT COIL

• Ignition ON, engine OFF.
• Suspect coil connector disconnected.
• Measure the voltage between:
  
  ( + ) COP Connector, Harness Side ( - ) Vehicle Battery
  IGN START/RUN Negative terminal
  

Is the voltage greater than 10 V?
Yes
GO to JF5 .
No
For all others, REPAIR the open circuit.
Clear the PCM DTCs. REPEAT the self-test.

JF5 CHECK THE SUSPECT COIL DRIVER CIRCUIT FOR AN OPEN IN THE HARNESS

• Ignition OFF.
• PCM connector disconnected.
• Suspect coil connector disconnected.
• Measure the resistance between:
  
  ( + ) PCM Connector, Harness Side ( - ) COP Connector, Harness Side
  Suspect coil driver COP

Is the resistance less than 5 ohms?
Yes
GO to JF6 .
No
REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.

JF6 CHECK THE SUSPECT COIL DRIVER CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS

• Ignition ON, engine OFF.
• Measure the voltage between:
  
  ( + ) PCM Connector, Harness Side ( - ) Vehicle Battery
  Suspect coil driver Negative terminal
  

Is the voltage less than 1 V?
Yes
GO to JF7 .
No
REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.

JF7 CHECK THE SUSPECT COIL DRIVER CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

• Ignition OFF.
• Measure the resistance between:
  
  ( + ) PCM Connector, Harness Side ( - ) Vehicle Battery
  Suspect coil driver Negative terminal
  

Is the resistance greater than 10K ohms?
Yes
GO to JF14 .
No
REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. If the concern or DTC is still present, GO to JF8 .

JF14 CHECK FOR CORRECT PCM OPERATION

• Disconnect all the PCM connectors.
• Visually inspect for:
  • pushed out pins
  • corrosion
• Connect all the PCM connectors and make sure they seat correctly.
• Carry out the PCM self-test.
• Verify the concern is still present.

Is the concern still present?
Yes
INSTALL a new PCM.
No
REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) , Programming the VID Block for a Replacement PCM. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

 

[CCXVI]

I'd definitely put money on a broken wire since I had everything apart. Thanks