ECU failed?

My lovely though troublesome Freelander 1 1.8 drove through a puddle and decided it had had enough, though I did manage to limp a couple of miles home to W London before the engine died completely.

The engine doesn't turn over at all but I'm assured there's nothing wrong mechanically. This is what comes up on the dash:


When I took this photo the engine was cold, the tyres pressurised and it was full of oil. But the good news is that the door was open and the handbrake was on!

The mechanic I called out suspected the ECU. Does that make sense? The ECU doesn't show any sign of damage/water etc.

Without towing it to a LR dealer and applying for a new mortgage, what are the steps needed to replace the ECU, keys and transponder, and reprogramming the replacement ECU?

Or is it time to say goodbye?

Thanks for any thoughts

Not 100%sure but isn't the ECU located inside the car , hopefully someone should be along soon to help you with more knowledge than I have on the freelander, hope you get it sorted soon

Editfinger said:

My lovely though troublesome Freelander 1 1.8 drove through a puddle and decided it had had enough, though I did manage to limp a couple of miles home to W London before the engine died completely.

The engine doesn't turn over at all but I'm assured there's nothing wrong mechanically. This is what comes up on the dash:
View attachment 305935

When I took this photo the engine was cold, the tyres pressurised and it was full of oil. But the good news is that the door was open and the handbrake was on!

The mechanic I called out suspected the ECU. Does that make sense? The ECU doesn't show any sign of damage/water etc.

Without towing it to a LR dealer and applying for a new mortgage, what are the steps needed to replace the ECU, keys and transponder, and reprogramming the replacement ECU?

Or is it time to say goodbye?

Thanks for any thoughts

Click to expand...

It's very unlikely to be the ECM. It's more likely to be a battery or charging issue.
The ECM is protected inside an environmentally sealed enclosure, so can't get wet.
The alternator is vulnerable to water ingress, as it's low down on the engine.
Alternator or battery is the most likely cause here.

Nodge68 said:

It's very unlikely to be the ECM. It's more likely to be a battery or charging issue.
The ECM is protected inside an environmentally sealed enclosure, so can't get wet.
The alternator is vulnerable to water ingress, as it's low down on the engine.
Alternator or battery is the most likely cause here.

Click to expand...

Thanks Nodge.

Yes the ecu is nicely hidden away from the elements. But I’m pretty sure both the battery and alternator have been checked. The engine doesn’t turn over at all - it doesn’t even try…

My initial thought was a short with an abs sensor or similar (under the wheel arch?), as it seemed to be after driving thru the rain. But could that stop the engine from turning over completely?

Have you lost the earth connection anywhere?

J_D said:

Have you lost the earth connection anywhere?

Click to expand...

Hi J_D,

Unfortunately that is above my pay grade. How would I check that? Most of the electrics - windows, lights, dash etc are still functioning....though come to think of it the cd player has gone into some sort of spasm....

Given that it all occurred when I went through water made me think that it was started by a short circuit. I had hoped that a bit of drying out would remedy it....but it didn't...

A failed ECM won't stop it from turning over, just prevent it from starting.
Does the starter click when the key is turned to the start position?
Have you checked the battery voltage? Alternator output can't be checked if the engine won't run.
A fault with the ABS won't stop it from running.
Your faults are very reminiscent of a dead battery.

Thanks Nodge,

The battery is only a year old and when the engine failed I had a voltage of 12V+. I tried to jump start but even then absolutely no starter click :-(

Editfinger said:

Thanks Nodge,

The battery is only a year old and when the engine failed I had a voltage of 12V+. I tried to jump start but even then absolutely no starter click :-(

Click to expand...

Check the spade end on the starter motor, it may also need new contacts inside, first check the spade end or earth point,

Hi Arctic2 I'll take a look at that...once I've packed the in-laws back off home....

I'm a new member here and I can't believe there are so many out there willing to help.

Thanks!

Why is temp gauge on max ?? Clue?

lol, the engine won't turn over, so investigate all the complex and unlikely causes first!

The first thing to do I'd have thought would be something like testing if there is a feed to the starter relay when the key is turned. If there is, then forget all your complicated possibilities, it'll be a 'normal' starting issue fault - ie relay, solenoid, brushes in the starter etc.

Nodge68 said:

A failed ECM won't stop it from turning over, just prevent it from starting.

Click to expand...

Is that strictly true?

The ECM doesn't control cranking, however, does it not need to send a coded key to the CCU or summat that does control the cranking and won't enable it (ie give the starter relay an earth) until it gets that key from the ECM.

Can't this be bypassed by giving the relay a permanent earth?

Similarly, the ECM won't enable injectors or ignition until it gets a similarly coded key from CCU or summat. This is not so easy to bypass!

andyfreelandy said:

Why is temp gauge on max ?? Clue

Click to expand...

I was thinking lost ground on ecu ??

GrumpyGel said:

Is that strictly true?

The ECM doesn't control cranking, however, does it not need to send a coded key to the CCU or summat that does control the cranking and won't enable it (ie give the starter relay an earth) until it gets that key from the ECM.

Can't this be bypassed by giving the relay a permanent earth?

Similarly, the ECM won't enable injectors or ignition until it gets a similarly coded key from CCU or summat. This is not so easy to bypass!

Click to expand...

The alarm ECU is what controls the immobiliser module IIRC. If the key doesn't match the immobiliser code, then start is inhibited by the alarm module, and there's a chime from the Ipack to warn if an issue.

It's a strange fault, which is pretty impossible to diagnose without being at the vehicle.