03 LS V6 with coil problems then PCM failure.. PCM module swappable?
jasonsjwou
07-29-2009, 10:05 AM
My father owns a '03 LS (V6) in Korea. He had no problem whatsoever with his LS for 6 years, until last week.
The engine stuttered horribly, and died. Could not get it restarted.
Towed the car to the Ford dealership in Seoul, Korea. They found out coils were bad. I know this is a common problem with LS... all coils and gaskets etc were replaced.
But it now says the PCM is bad. Car would not start up, throwing a code for PCM failure. The dealer had a bench tester PCM, so they put that in, then the car runs. So they determined PCM needs to be replaced.
I called the dealership with the part number, and they said it's on "national back order" with no promise of next release date.
I found several used PCMs for '03 V6 LS, but nothing exactly matches the part number of my Dad's LS. Close, but not exactly the same.
Can I use those?
The engine stuttered horribly, and died. Could not get it restarted.
Towed the car to the Ford dealership in Seoul, Korea. They found out coils were bad. I know this is a common problem with LS... all coils and gaskets etc were replaced.
But it now says the PCM is bad. Car would not start up, throwing a code for PCM failure. The dealer had a bench tester PCM, so they put that in, then the car runs. So they determined PCM needs to be replaced.
I called the dealership with the part number, and they said it's on "national back order" with no promise of next release date.
I found several used PCMs for '03 V6 LS, but nothing exactly matches the part number of my Dad's LS. Close, but not exactly the same.
Can I use those?
danielsatur
07-29-2009, 10:48 AM
1) Check fuse for PCM 1st!
2) Reseat + clean connectors going to the PCM.
A Tech can diagnose a Bad PCM or ECU when Not BAD!
* Get a used PCM from Ebay or a salvage yard for a LS V6 2003 or newer!
The Newer = Updated Flash memory.
I would consider a bench Test,or Try Testing PCM in another LS.
Please keep us informed of root cause + fix,so we can help others.
2) Reseat + clean connectors going to the PCM.
A Tech can diagnose a Bad PCM or ECU when Not BAD!
* Get a used PCM from Ebay or a salvage yard for a LS V6 2003 or newer!
The Newer = Updated Flash memory.
I would consider a bench Test,or Try Testing PCM in another LS.
Please keep us informed of root cause + fix,so we can help others.
jasonsjwou
07-29-2009, 11:28 AM
PCM from my father's LS is 3U7Z-12A650GTB
I found one that has 3W4A-12A650DG
Can I use this one?
I found one that has 3W4A-12A650DG
Can I use this one?
shorod
07-29-2009, 12:19 PM
I'm not sure where you could really find that information. He'd probably be okay if he replaced the PCM with one for a 2003-2006 with the same engine and transmission. There are probably significant differences between California models versus other US models as well. I'm not sure that anything would be different for a right hand drive car.
-Rod
-Rod
jasonsjwou
07-29-2009, 12:55 PM
I called around several ECM/PCM repair places and the all give different answers. One says yes while another one says it's better to send it in for repair.
That's probably what I'll do.
In Korea, cars are Left Hand drive, just like US. American cars can be imported to Korea without any modification - US DOT standards surpasses Korean DOT standards - i.e., Korean market is 100% open to all cars made in USA. No tariffs, No emission modification, No nothing.
Yet European cars outsell US cars by 4 to 1.
That's probably what I'll do.
In Korea, cars are Left Hand drive, just like US. American cars can be imported to Korea without any modification - US DOT standards surpasses Korean DOT standards - i.e., Korean market is 100% open to all cars made in USA. No tariffs, No emission modification, No nothing.
Yet European cars outsell US cars by 4 to 1.
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