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**Ewgoetz** · 05-26-2010, 10:21 PM

Fixed a issue with teh vacum leak my old brake booster was causing. Now I have another code which is

P1351 - Ign Diagnostic Monitor input Ckt

Any Ideas what could be the cause? engine seams to be running fine.

**Tony R** · 05-26-2010, 11:41 PM

Here is the Ford OBDII information

See page 31 for your code. Not sure if it helps much..
http://www.motorcraftservice.com/vdi...f/obdsm963.pdf

**Ewgoetz** · 05-28-2010, 01:11 PM

If there is not an IDM edge (coil firing) for every PIP edge (commanded spark event), the PCM will look for a pattern of failed IDM events to determine which ignition coil has failed. If the ignition coil cannot be identified or if the engine is running and there are no IDM edges, the IDM circuit is malfunctioning (P1351).

So how do I go about repairing this issue?

Actualy I think I know why the code is coming up now.
Before I did the Hydro brake booster swap I had a engine light coming up for a vacum leak cause my old vac brake booster was leaking. during that time as I was gathering parts stil for the hydro booster I had swaped out the ignition modulle, and it ran fine. looked at the old ignition module and new one and realized the last 2 alpha letters had been both different. I went over to teh dealer and had the parts guy run both numbers and the old one pointed to a different alpha letter as well. So I' waiting for tuesday to get here to get the new one that I need. I read on the board somewhere that thye had created 2 different Ign modules and one sends a signal to the ecm telling it that the spark had fired to the coil.

**miesk5** · 05-29-2010, 09:01 AM

yo,
I think you have it solved.
http://web.archive.org/web/200408281...80/ai_76665483
by David S in Motor Service, June, 2001 via web.archive.org

Should be Black in color for the CCD Type Module.

**miesk5** · 05-29-2010, 09:14 AM

Sorry, filed to add this due to lag by Comcast and I then I over-wrote it.

DTC P1351 Ignition Diagnostic Monitor Circuit Input Fault "...P1351 can occur if the Igniton Module was replaced with the Gray one instead of a Black one. The ICM Should be Black in color for the CCD Type Module. Many Ford parts sources are incorrect and show that this vehicle should have a Grey module. The Motorcraft part number for the Black ICM is a DY-679..."

05-26-2010, 10:21 PM	#1
Ewgoetz FSM Lifetime Join Date: Jan 2010 Location: Venice Posts: 472 iTrader: (1) Bronco Info: 1996 EB Bronco 5.8, E4OD, BW1356 Transfercase, 145,000Miles Ewgoetzs Garage	Engine light on Code P1351 Fixed a issue with teh vacum leak my old brake booster was causing. Now I have another code which is P1351 - Ign Diagnostic Monitor input Ckt Any Ideas what could be the cause? engine seams to be running fine.

05-26-2010, 11:41 PM	#2
Tony R Cleaning the trails Join Date: Oct 2006 Location: Alta Loma Ca Posts: 561 iTrader: (2) Bronco Info: 96 OBDII Forest Service Retired Tony Rs Garage	Here is the Ford OBDII information See page 31 for your code. Not sure if it helps much.. http://www.motorcraftservice.com/vdi...f/obdsm963.pdf __________________ 96 US Forestry Surplus Vehicle 5.8L XL 4" BDS Lift 35" Goodyear Wrangler SA KI6FGI

05-28-2010, 01:11 PM	#3
Ewgoetz FSM Lifetime Join Date: Jan 2010 Location: Venice Posts: 472 iTrader: (1) Bronco Info: 1996 EB Bronco 5.8, E4OD, BW1356 Transfercase, 145,000Miles Ewgoetzs Garage	If there is not an IDM edge (coil firing) for every PIP edge (commanded spark event), the PCM will look for a pattern of failed IDM events to determine which ignition coil has failed. If the ignition coil cannot be identified or if the engine is running and there are no IDM edges, the IDM circuit is malfunctioning (P1351). So how do I go about repairing this issue? Actualy I think I know why the code is coming up now. Before I did the Hydro brake booster swap I had a engine light coming up for a vacum leak cause my old vac brake booster was leaking. during that time as I was gathering parts stil for the hydro booster I had swaped out the ignition modulle, and it ran fine. looked at the old ignition module and new one and realized the last 2 alpha letters had been both different. I went over to teh dealer and had the parts guy run both numbers and the old one pointed to a different alpha letter as well. So I' waiting for tuesday to get here to get the new one that I need. I read on the board somewhere that thye had created 2 different Ign modules and one sends a signal to the ecm telling it that the spark had fired to the coil. Last edited by Ewgoetz; 05-28-2010 at 06:43 PM..

05-29-2010, 09:01 AM	#4
miesk5 I used to know this stuff Join Date: Oct 2003 Location: USE FORD PARTS, let da ZONE handle ice scrapers Posts: 4,599 iTrader: (1) Bronco Info: 96 XL 5.0 E4OD, Man Xfer/Hubs miesk5s Garage	yo, I think you have it solved. http://web.archive.org/web/200408281...80/ai_76665483 by David S in Motor Service, June, 2001 via web.archive.org Should be Black in color for the CCD Type Module. __________________ See our Big Bronco Technical, Parts Sources & Technical Service Bulletins Links site 96 XL 5.0 E4OD, Man Xfer/Hubs Our SF Site THANKS to ALL WHO SERVE!

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Engine light on Code P1351

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05-29-2010, 09:14 AM	#5
miesk5 I used to know this stuff Join Date: Oct 2003 Location: USE FORD PARTS, let da ZONE handle ice scrapers Posts: 4,599 iTrader: (1) Bronco Info: 96 XL 5.0 E4OD, Man Xfer/Hubs miesk5s Garage	Sorry, filed to add this due to lag by Comcast and I then I over-wrote it. DTC P1351 Ignition Diagnostic Monitor Circuit Input Fault "...P1351 can occur if the Igniton Module was replaced with the Gray one instead of a Black one. The ICM Should be Black in color for the CCD Type Module. Many Ford parts sources are incorrect and show that this vehicle should have a Grey module. The Motorcraft part number for the Black ICM is a DY-679..."