re: Won't Start [possible faulty ECU?]

Deckchair5 said:

Body computer?
That's behind the drop down panel next to the steering wheel, where you can see the fuses

I'd try an ECU reset by disconnecting the battery for an hour and see if it sorts itself out. I'd check if you've got a healthy 12.5v at the battery too whilst it's disconnected

Click to expand...

battery is good but will try the disconnect as well
first time posting today tho been a lurker for a while and would like to thank all for there replys

re: Won't Start [possible faulty ECU?]

Have you checked lives/earths at ECU yet? This would be the logical place to start.

re: Won't Start [possible faulty ECU?]

T14086 said:

Have you checked lives/earths at ECU yet? This would be the logical place to start.

Click to expand...

have got some but dont know what pins are what so dont know what i should have at each pin, need a diagram or list if you can help

also immob light comes on for about 2 secs then flashes 3 times then stays on permanatly. does that mean anything. can the ecu put this light on or just the body module. arial is working fine and all connections from body module to ecu seem ok

looking like ecu to me

re: Won't Start [possible faulty ECU?]

alphatune said:

looking like ecu to me

Click to expand...

Agree but you have to check supplies/earths beforehand...would look pretty silly if it was a fuse

re: Won't Start [possible faulty ECU?]

What engine is it? Then we can post you up the relevant ECU wiring diag

re: Won't Start [possible faulty ECU?]

I take it by user name 'alphatune you are a business? do you not have autodata?

If not decks will post up pic.

re: Won't Start [possible faulty ECU?]

adamcot said:

My car had somthing like this before I bought it! It was a non starter with immobiliser problems and then recovered to a dealership. It turned out to be an ECU failure and had a reconditioned unit replaced into it! Was expensive though, felt sorry for the previous owner at +£500 ish! Sorry to break the bad news!

Click to expand...

Had the exact same problem a couple of years ago. The car died at traffic lights. Just out of warranty, cost about £300 for a service exchange ECU,

re: Won't Start [possible faulty ECU?]

T14086 said:

I take it by user name 'alphatune you are a business? do you not have autodata?

If not decks will post up pic.

Click to expand...

i have autodata 2005 but it does not have pin data for the stilo
its a 51 plate 1.6
not a business anymore not for the last 5 years
if decks could that would be great

re: Won't Start [possible faulty ECU?]

+30 at connector A pin 16
+15 at connector A pin 29
-31 at connector B pins 5,6,21,22

re: Won't Start [possible faulty ECU?]

well a big thanks to all that have helped but especially decks for the ecu wiring diagram :worship:
went out this morning armed with the diagrams and an ocilliscope and found a signal wire missing and traced the fault to a broken wire, 2 mins to fix and car now running again

couldnt have done it without you guys so once again

THANKYOU ALL

re: Won't Start [possible faulty ECU?]

ITS BACK
had to take out the battery tray earlier to fix the passenger headlight levelling motor and put it all back together and now the same prob, bl***y car:bang:

re: Won't Start [possible faulty ECU?]

has anyone cut out the d4 plug and soldered the wires together as this would solve the corrosion prob

re: Won't Start [possible faulty ECU?]

you never said what the signal wire was?

re: Won't Start [possible faulty ECU?]

ok i have just spent hours out there and still i am getting no where

all wires from the underbonnet fuse box and both plugs behind the battery (d4 ) to the ecu are fine but still get the security failure loose connetion warning. all lives and earths are present so not really sure what else it could be. still cant read the ecu with a scanner tho i can read all other systems so dont know if i should bite the bullet and get a ecu
hope someone has a better idea
heres hoping

re: Won't Start [possible faulty ECU?]

did you check ECU lives & earths?..if so & ok then you have to be looking at ECU.

re: Won't Start [possible faulty ECU?]

yeah checked the lives and earths
just seems odd it was fine till i disconnected the fuse box and multi plugs to remove the battery tray to fix the headlight levelling motor, or maybe its leading me astray

re: Won't Start [possible faulty ECU?]

"loose connection" = "lost connection"
Everything was fine and you move the battery bay components with D4 connector and you get lost connection. Clues are there. Coincidence? Might be.

Think I'd try, as a test, jumpering the immobiliser security wires across the D4 connector. What might be making contact enough to make a connection at the connector may not be enough for fast communications. I'd back probe the terminals and connect them with a jumper

Are you REALLY sure the connection at the ignition aerial pick up ring is good? As there have been problems there in the past with a weak connection causing identical symptoms

ECU's arent cheap so I'd do the free stuff first

re: Won't Start [possible faulty ECU?]

Deckchair5 said:

"loose connection" = "lost connection"
Everything was fine and you move the battery bay components with D4 connector and you get lost connection. Clues are there. Coincidence? Might be.

Think I'd try, as a test, jumpering the immobiliser security wires across the D4 connector. What might be making contact enough to make a connection at the connector may not be enough for fast communications. I'd back probe the terminals and connect them with a jumper

Are you REALLY sure the connection at the ignition aerial pick up ring is good? As there have been problems there in the past with a weak connection causing identical symptoms

ECU's arent cheap so I'd do the free stuff first

Click to expand...

Ariel is defo good as when reading the immobilser or body modul it tells me how many keys and which one is inserted so seems ok
did back probe and seemed ok unless you have a different method to me
will try the jumper and see if that works

personally dont think its the ecu but i cant seem to find a wiring fault but will try one more time

thanks

re: Won't Start [possible faulty ECU?]

What I mean is to bypass the D4 connector, a bit like you were thinking of doing only not so permanent with a back probe on each side of the connector for the immobiliser wires and a jumper connecting the two. Then you can eliminate the D4 connector as a suspect

re: Won't Start [possible faulty ECU?]

i take it thats pins 36&52&20 & 51