Hi all,

 

i'm new here so hope this is the right place for this.

 

i have a 52 reg MkV i bought for my lads, and it's playing up somewhat.

 

symptoms are:

 

1) Speedo is intermittent

2) occasional dashed line accross the odometer

3) starter motor does not always engage

4) eats batteries (lost 0.3volts overnight on a brand new battery)

5) occasional EAC fail message on dash

 

I think most of these issues are related to the ECU located at the front of the battery, but i'm not 100% sure.

 

So if i can source a second hand one from ebay or a local breakers, is it just a straight plug and play, or does it need to be coded to the immobiliser, central locking ignition system etc etc?

 

Any help most appreciated

 

Mick

Might seem obvious, but have you bought this from a registered dealer? as it sounds like this is a fairly recent purchase. 

A replacement ECU would most certainly require reprogramming by an independent dealer.

12 minutes ago, Luke4efc said:

Might seem obvious, but have you bought this from a registered dealer? as it sounds like this is a fairly recent purchase. 

A replacement ECU would most certainly require reprogramming by an independent dealer.

No, had it about 9 months or so and was a private purchase, its only worth 300 or so, i'll probably end up having to work on it as a project!!!

 

thanks for the reply, not the one i wanted to hear, but thank you all the same

 

Mick

1 hour ago, mickstery said:

No, had it about 9 months or so and was a private purchase, its only worth 300 or so, i'll probably end up having to work on it as a project!!!

 

thanks for the reply, not the one i wanted to hear, but thank you all the same

 

Mick

My mate had Vauxhall and bought a refurbished ECU from ebay for £100 and had the keys etc. reprogrammed for about £30 (he knew the mechanic though). Should be similar price to a Ford, that is providing that the ECU is at fault and not a wiring loom problem!

7 hours ago, mickstery said:

1) Speedo is intermittent

2) occasional dashed line accross the odometer

3) starter motor does not always engage

4) eats batteries (lost 0.3volts overnight on a brand new battery)

5) occasional EAC fail message on dash

1st two faults are more likely to be Instrument cluster (IC) faults, or wiring (eg ECU to IC), or system voltage variations.

3) starter, if it turns but does not engage, is probably wiring, battery or starter solenoid. If it does not turn at all, it could be wiring between IC & ECU.

4) Current drain, could be a wiring fault keeping the ECU alive, or a radio or alarm system. Though losing 0.3 volts overnight only indicates a problem if it had been standing for at least 24 hours prior to the measured drop. Batteries will always drop slowly from the charge voltage of over 14v, to a rest voltage of 12.2v to 12.6v, over a period of several hours after the car has been used. It needs a current measurement to confirm current drain. A multimeter with a 10A range can be used, but care is needed to avoid loads like door locks from blowing the fuse.

5) Could be ECU or wiring loom, or system voltage.

So the battery (though I gather this has been changed) and the wiring looms seem to be the common elements here. I would investigate those before changing the ECU. I am fairly sure the PATS (immobiliser) settings are in the ECU. This can be a pig to re-programme, needing a programme like FORscan to do it. Or a good Auti-locksmith.