PCM fails twice in 62,000 km

'72 Bullet · 24th July 2022, 14:23

Hi All,

Greetings from Nepal!

So, the story is that we bought a Ford Fiesta Classic in December 2014. All was well till it suddenly broke-down while on the 20th of July 2018(~27,000 Km), we had it towed to the service centre in Kathmandu where they diagnosed it with a faulty PCM and instrument cluster. These were replaced at a cost of Rs. 80,000.

We assumed it was a one time thing that was resolved.

Last month(~62,000 Km), the car broke-down again and they are saying it is the PCM again and that we need to replace everything again. Since when has a PCM become a consumable that needs to be replaced every 30,000 Km. Has anyone else faced this issue?

We have taken it up with the local rep as well as with Ford-India but are just being stone-walled. has anyone else faced these issues?

Thank you very much for all your help.

vishy76 · 24th July 2022, 14:35

If the PCM has failed within such a short span of time, I would check the wiring harness. Something in the wiring harness or feeding inputs to the PCM might be overloading it and causing it to go bad.

I came across a Jetta which ate through 2 ECUs within a year's span. It turned out to be a rather complex issue. Coolant from the electronic connector on the temp sensor was entering the wiring harness and migrating into the ECM connector, shorting pins in the process and frying the ECM.

I am not saying your issue could be this complex, but start by checking the entire wiring in the engine bay including the ECM connector. Look for shorted wires or corroded pins (even signs of corrosion or water ingress) on the connector itself and sort this issue out for good before you go ahead and plonk another ECM.

'72 Bullet · 25th July 2022, 08:59

Quote:

Originally Posted by vishy76

If the PCM has failed within such a short span of time, I would check the wiring harness. Something in the wiring harness or feeding inputs to the PCM might be overloading it and causing it to go bad.

We have been checking but there's nothing obvious, the Ford service centre says they can't find any issues.

Another question, is it very complicated to fix a damaged PCM?

vishy76 · 5th August 2022, 02:20

Quote:

Originally Posted by '72 Bullet

We have been checking but there's nothing obvious, the Ford service centre says they can't find any issues.

Another question, is it very complicated to fix a damaged PCM?

Fixing a damaged PCM is a gamble. It entirely depends on what parts have gone bust. Some of the ICs used can be procured easily and replaced, some cannot.

24th July 2022, 14:23	#1
'72 Bullet BHPian Join Date: Dec 2008 Location: Semi-nomadic Posts: 143 Thanked: 11 Times	PCM fails twice in 62,000 km Hi All, Greetings from Nepal! So, the story is that we bought a Ford Fiesta Classic in December 2014. All was well till it suddenly broke-down while on the 20th of July 2018(~27,000 Km), we had it towed to the service centre in Kathmandu where they diagnosed it with a faulty PCM and instrument cluster. These were replaced at a cost of Rs. 80,000. We assumed it was a one time thing that was resolved. Last month(~62,000 Km), the car broke-down again and they are saying it is the PCM again and that we need to replace everything again. Since when has a PCM become a consumable that needs to be replaced every 30,000 Km. Has anyone else faced this issue? We have taken it up with the local rep as well as with Ford-India but are just being stone-walled. has anyone else faced these issues? Thank you very much for all your help.
	(4) Thanks

24th July 2022, 14:35	#2
vishy76 Senior - BHPian Join Date: May 2016 Location: N/A Posts: 1,296 Thanked: 10,294 Times View My Garage	re: PCM fails twice in 62,000 km If the PCM has failed within such a short span of time, I would check the wiring harness. Something in the wiring harness or feeding inputs to the PCM might be overloading it and causing it to go bad. I came across a Jetta which ate through 2 ECUs within a year's span. It turned out to be a rather complex issue. Coolant from the electronic connector on the temp sensor was entering the wiring harness and migrating into the ECM connector, shorting pins in the process and frying the ECM. I am not saying your issue could be this complex, but start by checking the entire wiring in the engine bay including the ECM connector. Look for shorted wires or corroded pins (even signs of corrosion or water ingress) on the connector itself and sort this issue out for good before you go ahead and plonk another ECM.
	(8) Thanks