Resistance too low ??

chicochapman · 5th December 2023, 13:31

ZTT 2.5 KV6 auto

I've just refitted the front seats after some upholstery work and now the screen is showing "airbag fault". Toaf is reporting it as " left hand pre-tensioner - resistance too low". I've re-made the under seat connectors again but no joy.
Does anybody have any thoughts on where I should look now?
Thanks,
Malc

vitesse · 5th December 2023, 13:37

Not sure if my memory is correct but I think someone said the tensioners are wired in series, so it could be one or the other.

Good luck

Devilish · 5th December 2023, 15:07

What does "re-made the under seat connectors again" mean exactly.
Unplugging plugging back does not guarantee a good connection.
The only way to be sure is to replace the connector with something of your choice.

If you still get the pre tensioner fault.

You may have disturbed the connection where the wire connects to the cartridge. you will need to remove the seat, disconnect the pre tensioner, and inspect it/re connect it.

SD1too · 5th December 2023, 15:34

Quote:

Originally Posted by vitesse

Not sure if my memory is correct but I think someone said the tensioners are wired in series, so it could be one or the other.

I've checked the wiring diagram and your memory is correct Mike as far as the front seat pre-tensioners are concerned (the rears are connected individually).

Simon

chicochapman · 5th December 2023, 16:04

What's puzzling me is that if it was a poor or broken connection I would have expected the fault to be reported as "high resistance".
Could "low resistence" possibly mean that I may have damaged a wire when putting the seats in and out and that there is a short at that point?

SD1too · 5th December 2023, 18:36

Although your thoughts make logical sense Malcolm, as you've been disconnecting things I would start by clearing the fault code and seeing if it returns.

Simon

chicochapman · 5th December 2023, 20:31

Unfortunately, the fault code is persisting. I'll tip the seat up tomorrow and inspect all the wiring. I'll report back.

chicochapman · 8th December 2023, 12:02

Well, schoolboy error I'm afraid. I had previously replaced the blue connector with two "bullet" connectors and when putting the seat back, I had pushed the yellow lead from the pre-tensionerout of sight and not thinking, I connected the two orange/brown wires together which put only one of the pre-tensioners in the circuit, hence the"low resistance" error.
Still, all better now!
Malc

ceetdm · 8th December 2023, 12:25

Glad you got it sorted - thanks for letting us know:-)

Tommy :-)

5th December 2023, 13:31	#1
chicochapman Avid contributor MG ZT-T Join Date: Feb 2019 Location: Stockport Posts: 138 Thanks: 56 Thanked 22 Times in 20 Posts	Resistance too low ?? ZTT 2.5 KV6 auto I've just refitted the front seats after some upholstery work and now the screen is showing "airbag fault". Toaf is reporting it as " left hand pre-tensioner - resistance too low". I've re-made the under seat connectors again but no joy. Does anybody have any thoughts on where I should look now? Thanks, Malc

5th December 2023, 15:07	#3
Devilish This is my second home 75 Tourer Join Date: Apr 2009 Location: Cannock Posts: 4,133 Thanks: 3 Thanked 189 Times in 121 Posts	What does "re-made the under seat connectors again" mean exactly. Unplugging plugging back does not guarantee a good connection. The only way to be sure is to replace the connector with something of your choice. If you still get the pre tensioner fault. You may have disturbed the connection where the wire connects to the cartridge. you will need to remove the seat, disconnect the pre tensioner, and inspect it/re connect it. __________________ If at first you don't succeed, hide the evidence

5th December 2023, 18:36	#6
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,520 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Although your thoughts make logical sense Malcolm, as you've been disconnecting things I would start by clearing the fault code and seeing if it returns. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

8th December 2023, 12:25	#9
ceetdm Loves to post Rover 75 CDTi Manual Saloon + Rover 75 CDTi Auto Saloon Join Date: May 2007 Location: Edinburgh Posts: 420 Thanks: 170 Thanked 42 Times in 33 Posts	Glad you got it sorted - thanks for letting us know:-) Tommy :-) __________________ Rover 75 Saloon CDTi Contemporary SE +pack

5th December 2023, 13:37	#2
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,556 Thanks: 395 Thanked 823 Times in 652 Posts	Not sure if my memory is correct but I think someone said the tensioners are wired in series, so it could be one or the other. Good luck

5th December 2023, 16:04	#5
chicochapman Avid contributor MG ZT-T Join Date: Feb 2019 Location: Stockport Posts: 138 Thanks: 56 Thanked 22 Times in 20 Posts	What's puzzling me is that if it was a poor or broken connection I would have expected the fault to be reported as "high resistance". Could "low resistence" possibly mean that I may have damaged a wire when putting the seats in and out and that there is a short at that point?

5th December 2023, 20:31	#7
chicochapman Avid contributor MG ZT-T Join Date: Feb 2019 Location: Stockport Posts: 138 Thanks: 56 Thanked 22 Times in 20 Posts	Unfortunately, the fault code is persisting. I'll tip the seat up tomorrow and inspect all the wiring. I'll report back.

8th December 2023, 12:02	#8
chicochapman Avid contributor MG ZT-T Join Date: Feb 2019 Location: Stockport Posts: 138 Thanks: 56 Thanked 22 Times in 20 Posts	Well, schoolboy error I'm afraid. I had previously replaced the blue connector with two "bullet" connectors and when putting the seat back, I had pushed the yellow lead from the pre-tensionerout of sight and not thinking, I connected the two orange/brown wires together which put only one of the pre-tensioners in the circuit, hence the"low resistance" error. Still, all better now! Malc