X20XEV Wiring Conversion

Post by **Robsey** » Sun Jan 22, 2023 12:16 pm

Hi All,

Just a quick query...

For the owners with the XEV engines, how do you get on for the ECU wiring diagram.?

I am helping a friend to wire up an X20XEV transplant engine into his wife's Cavalier SRi.
I am doing this via WhatsApp chat to his missus.

What we have found is that neither Haynes nor TIS show a schematic wiring diagram for the Simtec 56 ECU on the X20XEV for Cavalier or Calibra.

I find this quite odd as Haynes shows the C20LET, which is by far less common.

I am thinking that it must be a similar situation to the Cavalier V6's where you have to get a Vectra-B or Omega-B manual just for the engine related items.

Bringing it back to simple terms -
For the 2 litre XEV, is the Vectra-B Haynes manual / TIS the only sources of info?
Or does anyone know of a Cavalier specific diagram.?

Post by **Robsey** » Sun Jan 22, 2023 7:38 pm

I managed to find a diagram in Russian.

Looks like a quick learning curve to translate Russian motoring terms.

Post by **vexorg** » Mon Jan 23, 2023 9:29 am

The calibra does have the XEV diagram and no LET diagram, the only one I know of for the LET is the strange ozzie manual that does the rounds.

There are at least 3 version of the XEV setup on the calibra, with various emission options (egr etc) as they get newer

Post by **Robsey** » Mon Jan 23, 2023 8:57 pm

I presume that as the Calibra moved into the Vectra-B production years - 1996 to 98, that the wiring order changed completely again.

The Vectra-B wiring order looks nothing like that used on it's predecessor.

UPDATE / CORRECTION.

The Calibra and Vectra-B match until about 1998.
Then Vectra-B changes again - and this is why the TIS schematics do not match.
The Wiring Diagrams section only covers vehicles from 1998 onwards.

Thankfully after much trawling, older style drawings can be find in the Diagnostics section.
Diagnostics > Tech 1 > Engine > Simtec 56.5.

I cannot understand why Symtec didn't use a more rationalised approach to their ECUs.

Post by **vexorg** » Tue Jan 24, 2023 9:34 am

The calibra haynes have an early and late section, two full wiring drawing sets.
I've got them all scanned as pdf for convenience, since the text if getting a bit small for my old eyes!!

It's about 50Mb combined as the scan are all higher res so I canzoom into the small text.
I could upload it somewhere if you want to see.
I'm curious about the LET drawings you have too.

Post by **Robsey** » Wed Jan 25, 2023 8:13 am

There is a Haynes manual floating about on the tinterweb, but there are always chapters missing.
Usually clutch and transmission.

As most owners will know, schematics in the Haynes Cavalier manual (maroon book) are listed for 1989, 1991 and 1992 onwards.

I have found that if I go into my TIS2000 software and look at the Service Info, then Diagnostics - it does give a full pin-out listing for the Cavalier / Calibra with an issue date of 01/1994.
The schematic diagrams are far more blurred than the 30 year old Haynes manual print / ink.

The Vectra-B, the XEV schematics are easily found in the Wiring Diagrams section.

-

Old eyes!!

I know that one - my un-corrected focal length is approx 12" to 48". Anything outside that range, and it is either glasses or my phone camera to the rescue.

I have sent you my dropbox link, for my Cavalier / Calibra files, including V6 and LET stuff.

Post by **vexorg** » Wed Jan 25, 2023 9:26 am

Thanks, I used to have a dropbox account too, I'll see if it's still there, if notthen get a new one and upload that calibra wiring.

Post by **vexorg** » Thu Jan 26, 2023 1:13 pm

Thanks, grabbed your drawings, will look at them later when home.
I've uploaded the calibra ones too.

Post by **Robsey** » Thu Jan 26, 2023 3:43 pm

Likewise - I will have a good look through your file sometime over the weekend.

Thanks for sharing.

After a careful look, as expected, there is no 'early' XEV schematic.
Only in the later section.

A quick look at the first four pins, and it resembles the Vectra-B diagrams more closely - not the Cavalier listing on TIS.

Post by **Robsey** » Mon Jan 30, 2023 4:48 pm

It also states Simtec 56.5, rather than the more common 56.0 and 56.1.

Each is wired slightly differently.

You have got to love Vauxhall -

Post by **Robsey** » Sun Feb 05, 2023 10:04 pm

I have spent most of the day discussing relocating pins within the Cavalier loom to match the Vectra-B ECU.

What a total pain - even on a car without air-con, traction control and with a manual gearbox.
Made more complicated when using whatsapp.

The one thing that I noticed is that none of the schematics displayed any links from the ECUs to the immobiliser ring or alarm / anti-theft unit.

Only between the immobiliser ring and alarm / anti-theft modules.

So it makes you wonder how that works.?

Even when an alarm / anti-theft unit is not fitted from the factory.

Cavaliers can come with a bypass cover for the alarm connector... and the vectra-b can come with just remote locking without anti-theft warning.
(Kiekert unit).

Update - the only link I can see is the KWP diagnostic wire -
On the Cav, that is ALDL pin G
On the later cars, that is EOBD2 pin 7
All modules share that wire...

Post by **vexorg** » Tue Feb 07, 2023 9:45 am

The WEG line is the communication between ecu and immobiliser, I dont believe the anti-theft is connected to the main ecu at all on the older cars (even the newer ones, vectra b,I think the antitheft disables when the ignition turns on).

Post by **Robsey** » Tue Feb 07, 2023 7:04 pm

WEG?
That is odd, because Weg is German for wheel or something like that.
It is the road speed pulse signal.

Either way, as long as there is a link between the ECU and the immobiliser.

Post by **vexorg** » Wed Feb 08, 2023 9:45 am

On the drawing I sent, the later one has the XEV, ref 151 at the top has the weg line that runs to the immobiliser ecu K117 on ref 760. Blue with a red stripe.

Post by **Robsey** » Wed Feb 08, 2023 12:57 pm

Yes it does...
I presume that this is to stop the immobiliser kicking in when the car is moving.

Not something I would want at motorway speeds.

I hope that my loom conversion tables will be enough to get the car running in the next week or two.

Post by **vexorg** » Wed Feb 08, 2023 1:15 pm

As far as I know it only works whenyou put the key in and turn the ignition on. It's sends a secret code to the engine ecu to say the correct key chip has been detected, then the ecu will start.

The older programmers let you put a new immobiliser code into the engine ecu if you change it.

Post by **Robsey** » Sat Feb 11, 2023 9:00 pm

I have had a look at how the immobiliser works the ecu.
Obviously I won't say too much on a public facing forum.

But from what I can tell, the immobiliser disables the fuel pump and some sensors....
But the fuel injector valves and other sensors still get power with the ignition on.

I have also found a way to do away with the troublesome dual-relay fuel injector / pump relay.

Wiring up in the same way as the Vectra-B with two 'standard' four-pin relays means that if you do have an issue, you can replace with a much cheaper and more reliable off-the-shelf relay... or two.

Post by **Robsey** » Sat Feb 11, 2023 9:09 pm

Pin numbers vary between Simtec and Motronic, but the idea and relay configuration is the same.

And converted to two separate relays.

Post by **Robsey** » Sun Feb 19, 2023 12:38 pm

Well after much stress and many sleepless nights, the owner has waved the white flag.

It appears that converting the XEV ECU plug is simply too much for them to manage.

So the loom will be coming to Robsey Villas where I shall bell out the wires, and carry out any repairs and pin re-assignment,

before posting it back again.

Sounds like my next few Sunday mornings are booked up. - lol.

By the way...
I now have about five different pin-out versions dependent upon model, ECU Firmware, and information source.

Strangely Haynes schematics seem more reliable than those supplied by Vauxhall in TIS2000.

The TIS schematics DO NOT match their own pin listings in the diagnostics section of the software.

It makes you wonder how Vauxhall technicians ever fixed anything if the electronic database is not consistent and correct.

Post by **vexorg** » Sun Feb 19, 2023 6:43 pm

I know on the calibra there were at least 3 versions of the xev. Some had EGR, some had SAI, early ones had none of that.

Post by **Robsey** » Sun Feb 19, 2023 6:54 pm

Yep - the Vectra has ground triggers for both.
Oh fun.
Strangely the same ECU (RT) part number for all X20XEV Vectras from 1996 to 2002.

Post by **vexorg** » Sun Feb 19, 2023 6:59 pm

I think when the vectra came along then they had settled on what it should have, and the same as the last of the calibras.

Post by **Robsey** » Sun Feb 19, 2023 7:50 pm

It is just odd that they swapped sensor pin positions too.

On at least two sensors the pin numbers on the sensors are different between Cavalier and Vectra-B.

I have heard of a few cars not running following sensor replacement due to a different pin arrangement.
Which Vauxhall accidentally forgot about when listing some replacement part numbers (superceded / updated parts).

Post by **Robsey** » Mon Feb 20, 2023 11:02 pm

For those who have a Cavalier with X20XEV.

Fill yer boots.

Schematic.

Pin Listing.

Post by **Robsey** » Sat Mar 04, 2023 10:13 am

A small box ....
Okay a big box arrived on Wednesday.
It sat in the boot of the car until last night.

I looked inside the box this morning, and my heart sank.

I think it is at least one whole Cavalier X20XEV loom plus spares for me to repair and reconfigure to fit the Vectra-B ECU.

Oh chuff - what have I slotted myself up for?

A sandwich and a cuppa to wake up my brain before I try to sort this mess.
No wonder my friend got overwhelmed by it all, and gave up.

Just building up my will to live - lol. Yeeesh!!

At least when I did my NE in 2012, it was only reconfiguring the earth wires to convert from auto to manual.