Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > XC90 '02'15 General
Register Members CarsBlogs Help Calendar Mark Forums Read

Notices

XC90 '02'15 General Forum for the Volvo XC90 Phase 1 Series

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

Finding short in LIN any advice

Views : 223

Replies : 7

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Feb 11th, 2018, 11:37   #1
osullivant
Senior Member
 

Last Online: Jul 30th, 2018 18:14
Join Date: Jul 2011
Location: cork
Default Finding short in LIN any advice

VIDA suggests I have a short in the LIN that has taken out the SWM I have looked around the SWM and the CEM and can not see anything obviously amiss.

Can anyone suggest how I might narrow down this search....
osullivant is offline   Reply With Quote
Old Feb 11th, 2018, 13:00   #2
SwissXC90
Premier Member
 

Last Online: Today 08:54
Join Date: Jan 2016
Location: Cross Country
Default

Easy

Get the wiring diagram for your model Volvo.
if the exact MY is not available, a year before or after doesn't matter. As long as the diagram is pre-facelift or post-facelift to match your car.

Look at the LIN bus wiring from the SWM
See what connectors it goes to
Measure resistance of LIN bus to ground with everything connected.
If VIDA is correct, it will be 0 ohms to ground (of something close to 0)
Then start disconnecting the connectors until you have isolated the fault

Example of MY2009 XC90:
The CEM connects directly to the SWM via LIN
The SWM connects to the Clockspring via LIN
The Clockspring connects to the Left buttons and the Right buttons via LIN

In electronics repair there is a saying: "if it moves, it breaks"
Thus suspect #1 is always the Clockspring.

Unplug the Clockspring from the SWM and see if the short disappears
If so, plug it back in, and then unplug the buttons in the steering wheel and see if the short disappears
If so, the Clockspring is the culprit
__________________
XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.
SwissXC90 is offline   Reply With Quote
Old Feb 11th, 2018, 15:09   #3
osullivant
Senior Member
 

Last Online: Jul 30th, 2018 18:14
Join Date: Jul 2011
Location: cork
Default

thanks, very logical... try tomorrow...

for this to work should it be work key out? ... battery disconnected?
osullivant is offline   Reply With Quote
Old Feb 11th, 2018, 16:10   #4
volvo for ever
Master Member
 

Last Online: Aug 12th, 2018 13:12
Join Date: Apr 2015
Location: uk
Default

i would doubt youve lost lin signal at swm

what is your fault whats not working...... lin signal should be 7- 9 volts

please update with faults
volvo for ever is offline   Reply With Quote
Old Feb 11th, 2018, 17:11   #5
SwissXC90
Premier Member
 

Last Online: Today 08:54
Join Date: Jan 2016
Location: Cross Country
Default

Quote:
Originally Posted by osullivant View Post
for this to work should it be work key out? ... battery disconnected?
You can measure voltage with key on. As volvo_for_ever said, an active LIN bus sits around 7 to 9V DC when measured with a normal multimeter

If shorted you would see something around 0VDC

Tip:
The SWM is active from the moment you press a remote button to unlock the vehicle. And stays active continuously until the vehicle goes into sleep mode around 30s after closing and locking the vehicle, provided no buttons are pressed or functions activated


NOTE
Unplugging anything going to the steering wheel WILL cause an airbag fault to trigger when the steering wheel airbag is no longer detected.

It is not easy or visible to tell when the vehicle is properly asleep - and during any time it has woken up it monitors airbag systems.

So either prepare yourself with VIDA, or do all diagnoses with the vehicle battery disconnected and using an ohmmeter.
Observe battery disconnect precautions:
Remove key, close all doors, open tailgate, wait 10min tailgate light goes off by itself
The the car is asleep and you can disconnect the battery safely.
Always remove negative cable (black).

When reconnecting, the Volvo advice is to have key in PosI, and NO person in any seats (to ensure no airbags will trigger, as they only trigger when the seat is occupied), then attach battery promptly.
__________________
XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.
SwissXC90 is offline   Reply With Quote
The Following User Says Thank You to SwissXC90 For This Useful Post:
Old Feb 13th, 2018, 18:42   #6
osullivant
Senior Member
 

Last Online: Jul 30th, 2018 18:14
Join Date: Jul 2011
Location: cork
Default

So removed airbag and unplugged steering wheel controls from clocklspring, problem solved,

unplugged cruise control and plugged back in controls, problem remained solved.

Took board out of cruise control, no signs of stuck switch or burnt component or even corrosion but undoubtedly this is the problem. replaced everything with bunch of tissue in place of faulty board and all is good in Volvoworld for now..

Thanks again to SwissXC90.
osullivant is offline   Reply With Quote
The Following 2 Users Say Thank You to osullivant For This Useful Post:
Old Feb 13th, 2018, 20:58   #7
SwissXC90
Premier Member
 

Last Online: Today 08:54
Join Date: Jan 2016
Location: Cross Country
Default

Always a delight to hear that my advice led to a prompt and successful repair!

You can pickup replacement cruise control buttons on eBay cheaply.
(unless you want to start diagnosing where the short is on the cruise control button board....)
__________________
XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.
SwissXC90 is offline   Reply With Quote
Old Feb 13th, 2018, 23:00   #8
osullivant
Senior Member
 

Last Online: Jul 30th, 2018 18:14
Join Date: Jul 2011
Location: cork
Default

Quote:
Originally Posted by SwissXC90 View Post
Always a delight to hear that my advice led to a prompt and successful repair!

You can pickup replacement cruise control buttons on eBay cheaply.
(unless you want to start diagnosing where the short is on the cruise control button board....)
Ill pick one up here on adverts.ie

This country is full of xc90s being taken apart because of high road tax 1038 per year and high if not impossible insurance and really silly dealer prices for repairs...
osullivant is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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 +1. The time now is 11:58.


Powered by vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.