Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 25th March 2020, 21:56   #1
chicochapman
Avid contributor
 
MG ZT-T

Join Date: Feb 2019
Location: Stockport
Posts: 130
Thanks: 56
Thanked 22 Times in 20 Posts
Default Problem "ECU not present or not connected"

Toaf won't talk to my airbag ECU. It reads everything else.
T4 won't connect either as I've been to see BigRuss a couple of times last year.
So I decided to do a bit of continuity testing but first job access the ECU
Fortunately I'd watched Russ do this and more fortunately, the fixing bolts down
by the side of each seat hadn't been replaced by a previous owner, so I was able
to get at it without removing the seats, the whole centre console as well as avoiding
sruggling with the gear knob. Still fiddly to undo the torx fasteners holding the DCU in place
but a bent 1/8thW ring spanner(pictured) came in useful!






To facilitate the point to point testing I made up these leads terminating in a stub
of guitar string of matching diameter.





First up was the K-Bus, testing for continuity between Cavity 7 of the diagnostic
socket(C0040) and cavity 9 of the harness connector (C0256) – all good.
Next tested for12V+ on cavity 5 of the harness connector – all good and then
tested the ground on cavity 6 – all good.
I had a new identical spare unit (YWC 107090) which I fitted but still Toaf wouldn't read it.


So I've still got the annoying airbag warning light and because I can't connect to the DCU,
no means of finding where the fault is.


Any help would be much appreciated.
Malc
chicochapman is offline   Reply With Quote
Old 25th March 2020, 22:52   #2
vitesse
I really should get out more.......
 
Rover 75 Saloon

Join Date: Jul 2011
Location: Gävle
Posts: 2,516
Thanks: 395
Thanked 823 Times in 652 Posts
Default

Standard Toaf will only read the airbags up until about 2002 and then Rover started using Autoliv. As your car is a later model you have to, if you haven't already tried, use the SRS Autoliv Tool available from the Toaf website. Another complication is that the tool requires Vista or higher to run it, but it works.

Regards
vitesse is offline   Reply With Quote
Old 26th March 2020, 08:12   #3
marinabrian
 
marinabrian's Avatar
 
MG ZT

Join Date: Jan 2011
Location: Newcastle Upon Tyne
Posts: 20,151
Thanks: 3,565
Thanked 10,837 Times in 5,718 Posts
Default

If you've tried to connect to the SRS DCU with it hanging on the connector like that, you can now throw it in the bin.

If power is applied to the SRS DCU without it being correctly earthed, it automatically logs it as crash data, and is scrap.

The connector must be unplugged, before the unit is unbolted, and the secondary earthing strap removed.

Fuse 12 in the passenger compartment fusebox is often removed by people attempting to "bypass" the SRS system, which results in non communication with T4, TOAF in standard format has an issue communication with the Autoliv system fitted to your car.

Time for another DCU I'm afraid

Brian
marinabrian is offline   Reply With Quote
Old 26th March 2020, 17:32   #4
chicochapman
Avid contributor
 
MG ZT-T

Join Date: Feb 2019
Location: Stockport
Posts: 130
Thanks: 56
Thanked 22 Times in 20 Posts
Default

Thanks very much for that Brian. Just never occurred to me that you could "fry" these things. Does a new one (£) have to be paired with the car and if so do you know if it can be done with Toaf?
Thanks again,
Malcolm
chicochapman is offline   Reply With Quote
Old 26th March 2020, 17:39   #5
chicochapman
Avid contributor
 
MG ZT-T

Join Date: Feb 2019
Location: Stockport
Posts: 130
Thanks: 56
Thanked 22 Times in 20 Posts
Default

Quote:
Originally Posted by vitesse View Post
Standard Toaf will only read the airbags up until about 2002 and then Rover started using Autoliv. As your car is a later model you have to, if you haven't already tried, use the SRS Autoliv Tool available from the Toaf website. Another complication is that the tool requires Vista or higher to run it, but it works.

Regards

Thanks for the info. The "off assembly" date for my car was 2nd Sept 2002
so having downloaded the Toaf SRS tool, I'll try that first - after, that is I've bought a new DCU and managed to install it safely!!
chicochapman is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 20:17.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd