Plug & play ecu advice/info needed

[Brown]

Looking into getting a plug & play ecu (immo off) to see if it fixes issue I've been getting.
Can anyone tell me please:

1, do I need to get one specifically for automatic or does this make no difference As long as numbers match,?

2, if it turns out that it's my bsi (under the dash) that needs replacing does that mean I wouldn't need it programing/coding due to the plug & play ecu ?

3, is It right that the engine bay bsm fuse box Can be replaced without the need for any programing/coding on a 2008 mk1 c4 1.6 vtr+hdi auto,?
Any info or advice welcomed & appreciated
Thanks in advance

[wheeler]

What are the issues you are having?

Looking into getting a plug & play ecu (immo off) to see if it fixes issue I've been getting.
Can anyone tell me please:

1, do I need to get one specifically for automatic or does this make no difference As long as numbers match,?

I wouldnt think so as the ECU is configured as auto or manual, so you would need to configure it.

2, if it turns out that it's my bsi (under the dash) that needs replacing does that mean I wouldn't need it programming/coding due to the plug & play ecu ?

I expect the car would start but you will loose your remotes & some configuration would be needed as your radio (assuming its the original) will be beeping too.
I take is you are aware of milage issues when fitting a used BSI?
I would think best to get a matched ECU, BSI & key set to begin with.

3, is It right that the engine bay bsm fuse box Can be replaced without the need for any programming/coding on a 2008 mk1 c4 1.6 vtr+hdi auto,?

Yes that is correct.

[Brown]

Issue is as follows: not sure how to link to earlier topic soo I'll copy n paste below .
VF7**************[VIN obfuscated, can be read by forum staff]**************[VIN obfuscated, can be read by forum staff]
2008 citroen c4 coupe 1.6 vtr+ hdi auto 109hp.

Help/advice needed please
Car was running & driving fine, when suddenly engine light came on with allsorts of warnings on dash ie dpf system faulty,auto gearbox faulty abs, esp faulty probably other stuff but can't right remember.
Car didn't want to respond to throttle so pulled into layby just as Car engine stalled and cooling fan kicked in. I gave car a quick look over but couldn't see anything out of order so tried to restart car several times,car kept starting but cutting straight out. All the time radiator fan was at full bore.
So I disconnect battery to stop radiator fan from running & left it for 10 -15 mins.
Re connected battery back up and after a few failed attempts where engine would fire up then instantly cut out it fired up and drove like nothing had ever happened, other than the engine light being on. So drove it home about 5 miles ish with no problems parked it up at back of house till I could investigate problem further. Day after I started car 1st turn off key like usual left it running for 15 -20 mins read & cleared codes, car showed no signs of any problems
Couple of days went by (waiting for weather to sort itself out) went out started car again 1st turn of key started & ticked over lovely, but after about 15-20 mins car cut out threw loads of warning lights & messages up & radiator fan went full bore again. So took key out waited 5 mins fan was still going so disconnected battery & waited 20-30mins reconnected battery but ever since the engine just keeps starting then instantly cutting out, been like this for a couple of weeks now.
Checked for dodgey wires & fuses but all look good, wiped codes a few times, checked earth's to body,unplugged & cleaned any & every connector I can find, cleaned egr valve replaced fuel pressure sensor. Charged battery.Done some wiggle tests & unplugged various sensors but Still doing same thing, starts 1st turn of key then cuts out. Below are a list of trouble codes that keep coming back.:

P0606
State: intermittent
ECU1 fault inside ECU

P1166
State: intermittent
Fuel high pressure regulation. Maximum Rail pressure exceeded.

P1457
State: Permanent
Exhaust differential pressure sensor signal
Particulate filter punctured or abscent.

P2142
Air mixer control : Short circuit to positive

0015 no communication with engine ECU

Also had various intermittent codes relating to egr valve & such but those top 3 codes seem to always come back. where as others seem more random

Wondering if it's worth trying 2nd hand ECU or BSM unit was thinking immo off option to save programing.or if it's worth trying other parts 1st
Any help or advice much appreciated.

[Brown]

1,What's the milage issue ?
2,what is needed to make up a matching set ?
3,what is needed to make the necessary configuration changes.?

[wheeler]

1,What's the milage issue ?
2,what is needed to make up a matching set ?
3,what is needed to make the necessary configuration changes.?

1. The milage on this car is stored in both the instrument panel & BSI, if you fit a BSI from another car that has a higher milage than yours your car will permanently inherit the higher miles, even if you switch your original BSI back in again.

2. A matching set is the injection ECU, BSI & key from the same car, these are all matched together. Means you wouldn’t need to immo off.

3. Lexia/Diagbox or another high end diag tool.

Another option is to have the immo data on your ECU cloned onto a used one. Cant see the BSI causing this type of fault. Have you unplugged the ECU to check for dampness on the connectors?

[Brown]

Thanks for the info much appreciated.
One of first things I thought was maybe water got into electrics somewhere as it happend day after car had been sat in 2 to 3 days of heavy rain but everything looked dry.
Yes I've unplugged and checked connectors to ecu & engine bay fuse box, also any other connectors I could find all looked good clean & dry also checked & cleaned any fuses I could find. Unwrapped & followed wires as far as I can get but all look good so far. Cleaned egr valve replaced fuel pressure sensor and regulator still exact same symptoms,
Main 3 codes that keep coming back after clearing & trying to restart engine are:
P0606
State: intermittent
ECU1 fault inside ECU

P1166
State: intermittent
Fuel high pressure regulation. Maximum Rail pressure exceeded.

P1457
State: Permanent
Exhaust differential pressure sensor signal
Particulate filter punctured or abscent.

[Brown]

Just found this in an old thread from someone who had same p1166 code on c2 1.6 hdi 9hz engine which I believe is same engine as mine.
See below::

(To update this thread in case anyone else will have the same issue in the future with the 1.6 HDI. Believe it or not, it was the BSM. There was a TSB from Citroen which referenced the DTC I had and the TSB stated the BSMs have a manufacturing issue.

The old BSM had a couple of relays which turned black (looked like from smoke or somethign similar).

I fitted a new BSM and the car has been fine since (this was a good few months ago))..

They too was having engine cut out issues until changed BSM. I can't see any blackened relays though but might be worth a try.

[Brown]

Also do you know if there is a way to check the relay before replacing bsm ?