MEV Rocket Immobiliser Issues

[chris_c201]

Hi Folks,

As it's based on a Ford Focus i've duplicated this post in the Ford forum.

I put my car in to get a wheel bearing done and they phoned to say it wouldn't start, immobiliser LED flashing rapidly. Took spare key down, same thing. Turned out the ring that goes round the ignition barrel (PATS transceiver i believe it's actually called) was shot so they replaced, car started.... only thing is the transceiver was heating up and when it was turned off and back on, back to square 1, rapidly flashing LED.

Auto spark (Porsche garage!) has been eliminating things and it appears earch is ok, the feed from the transceiver to ECU and back are continuous and even compared voltages in the MEV vs. a Ford Focus and all appears to tie up (9.9v going back to the transceiver).

Thought perhaps it was an ECU fault and i happen to have a spare (beauty of a kit car with parts!) so switched it out and exact same thing happened.

I've only had the car 2 weeks (1 of which its been in garage for this issue!) and i didn't build it so not even had a chance to really get under the skin of it. Old owner (also built it) has been really helpful but drawing a blank plus he's 300 miles away!.

Any input gratefully received.
Chris

[ColinM50]

chris_c201 said:

I've only had the car 2 weeks (1 of which its been in garage for this issue!) and i didn't build it so not even had a chance to really get under the skin of it. Old owner (also built it) has been really helpful but drawing a blank plus he's 300 miles away!.

Any input gratefully received.
Chris

Perhaps that's why he sold it? Sell it?

[NoCorseChris]

Hopefully you will get some specific knowledge from the Ford crowd, but thinking generally about this. Does your car completely replicate the Ford setup of the system including the column, switchgear etc? Is it a true copy of the wiring between the pertinent systems? Is struck me that possibly there is some physical difference that is causing the coil on the lock to RF-couple with something nearby and that in turn is overloading it. Real straw-clutching I know, but it is a pretty weird problem at first look.

Wiring wise, it'll be hard no doubt, but I'd say you really need to make sure it truly is wired as per the donor was. No 'convenient' shortcuts to pick up power or the like. It could be that the immob system only gets energised for a brief time normally, but in your kit has been wired to permanent power?

Good luck anyway and please keep us posted.

[ikarl]

I know Chris isn't on here often, but I'm pretty sure the issue has been fixed

It was a corroded earth strap, new strap and all's good!

[ADEuk]

Blimey in the old days it used to be the choke cable glowing red hot when cranking, now you get roasted plums instead!

[chris_c201]

All sorted as Karl said, thanks for the suggestions above though! Symptoms were pretty random and for two days the garage were drawing a blank (said they'd already tested earth, waiting on pictures that show what exact issue was) so just glad to have it home!

[NoCorseChris]

Ah, good news. Had the clutch slave hydraulic line glowing red once due to a bad engine earth, it was a braided stainless over PTFE line by the way, not conductive rubber

Tend to see all manner of odd issues with bad earths on modern cars now - I should have thought of that one!