ECU Problems :(

eprothe said:

Hello,
Apologies for not replying sooner - I've been snowed in for six weeks and couldn't do any proper testing!

So, here's some Scottish landscape, enhanced with my Defender, which now has 100 miles behind it on new capacitors!
View attachment 232039

Obviously, I wouldn't say this within earshot of my ECU, but the new cap's do seem to have fixed it

Apart from all the ignorable errors, my ECU is still throwing a 160,CAN Error which I have no idea about...and now it's complaining that the EGR valve is stuck open (I removed it, years ago...not sure why it's only now throwing an error).

I'm sorry to read the misery you're having with your ECU, Brown - I think I've been very lucky with mine (so far)!

I like the idea of a 3d printed cradle for replacement cap's - eminently do-able! I have my eye out for a cheap, dead ECU on eBay as a test subject

All the best

Click to expand...

Thats good news, hope it keeps going and proves to be a lasting solution
As I have said before this has to become a growing market with quite a few TD5s arround and the ECUs getting older,

Is your fixed ECU still working? I'm tempted to try this myself...

Thanks

Hello,

apologies for not replying sooner. I'd always meant to update this with how things are going...

The best part of a year later and something like 5000 miles down the road, I've never had another ECU fault since I changed the capacitors. In fact, until my starter may or may not have packed up a couple of days ago, I've had no problems at all!

The trickiest bits of the fix were getting the cover off the ECU without damaging it and then getting the old capacitors out - I had to cut through the mounting brackets, as I couldn't see any other way of doing it. If I did it again, I'd use longer wires on the capacitors to give them a bit more play for positioning.

I'd say go for it - what have you got to lose?

lt's definitely do-able

My Ferrari had two ECU's, one for each bank of the V8. l had an issue with one of them, and it was going to cost over £1,000 for a service replacement.

l took the unit apart and replaced three electrolytic capacitors which looked past their best. The top had swollen on one of them.

lt does require a degree of electronic competence, the PCB is plated through (the components are soldered right through the hole in the PCB and not just on the surface)

So you need to be careful removing the old parts, de soldering wick is useful and you also need a decent soldering iron, preferably a soldering station.

Anyhow, l re fitted the ECU and the engine ran fine after that, saving me £1,000.
Bear in mind that these ECU's will most likely be exchange, as mine was, so if you wreck yours trying to change components they might not accept it as an exchange unit.

did you try https://www.hificollective.co.uk/components/evox-rifa-capacitors.html

Although it's tempting to leave longer leads on the new components, it's important to mount them directly on the PCB.
There are a couple of reasons, to do with resonance and vibration, and to a lesser extent electromechanical and RF pickup on exposed unscreened wiring.

eprothe said:

Hello,

apologies for not replying sooner. I'd always meant to update this with how things are going...

The best part of a year later and something like 5000 miles down the road, I've never had another ECU fault since I changed the capacitors. In fact, until my starter may or may not have packed up a couple of days ago, I've had no problems at all!

The trickiest bits of the fix were getting the cover off the ECU without damaging it and then getting the old capacitors out - I had to cut through the mounting brackets, as I couldn't see any other way of doing it. If I did it again, I'd use longer wires on the capacitors to give them a bit more play for positioning.

I'd say go for it - what have you got to lose?

Click to expand...

Thanks for the update. I think I'll give it a go. Fingers crossed!

Got the lid off thanks to some brute force and ignorance, and it all looks really good in there, apart from some corrosion on one of the big nuts holding one of the caps in place.

Next step is to try and remove the old caps without breaking something

lightning said:

Although it's tempting to leave longer leads on the new components, it's important to mount them directly on the PCB.
There are a couple of reasons, to do with resonance and vibration, and to a lesser extent electromechanical and RF pickup on exposed unscreened wiring.

Click to expand...

Yep, this is a good point - mucking about with what's essentially a single-board computer is fraught with risk!

I'd be interested to know what the frequency the two capacitors are being used at is, though - they're both so large, I can't imagine it's very high and I'd be surprised if any RF issues raised themselves, likewise resonance effects, even with five or six cm of wiring to the terminals, the inductance of the wires is going be practically nothing - well down in the nH range. Unfortunately, mounting new capacitors directly to the PCB isn't possible without modifying the PCB itself and the risk of damage really wouldn't be worth it.

I hot-glued the capacitors to the original mounts in my ECU, as the new capacitors didn't have mounting lugs but I quite agree - I wouldn't leave them rattling about inside the ECU unsecured.

I managed to find almost perfect replacement capacitors, with screw terminals, and after easing the oversized one in, I gave my repaired ECU a test today...

...it didn't work. Same no-start, non-firing issue as before.

Does anyone know if I need to hook a nanocom up and clear the fault codes (topside switch failure and injector open circuit) before it will work, or should it have worked straight away?

Needless to say, I don't have a nanocom...

Cheers

BulletBrindle said:

I managed to find almost perfect replacement capacitors, with screw terminals, and after easing the oversized one in, I gave my repaired ECU a test today...

...it didn't work. Same no-start, non-firing issue as before.

Does anyone know if I need to hook a nanocom up and clear the fault codes (topside switch failure and injector open circuit) before it will work, or should it have worked straight away?

Needless to say, I don't have a nanocom...

Cheers

Click to expand...

No, there is no need to delete fault codes for it to have run.

I thought that was the case, but sometimes you gotta clutch at those straws!

Does anyone have any ideas on what I should check next?

Cheers

It works!

I made the mistake of reusing the original bolts that held the caps in place, even though they weren't in the cleanest condition. New bolts fitted, and it fires up like a dream.

Now for a few proper road tests before calling this a win.

Well done, you've saved yourself the £400-£700 it costs for a replacement ECU.

I popped a post together to describe what I did, in case anyone else wants to give it a try...

https://www.landyzone.co.uk/land-ro...th-doing-for-preventative-reasons-too.378202/

It's now in the truck for a long term test (along with the spare, just in case)

On my ECU it wasn't that, it was one of the surface mount resistors near the processor IC.

lightning said:

On my ECU it wasn't that, it was one of the surface mount resistors near the processor IC.

Click to expand...

Yep, I certainly was fortunate that it was the caps and not any of the surface mount components.

I feel pretty confident that this is a permanent fix for me, but let's see what the next few thousand miles brings...