Brake lights coming on wiith park lights ?? - Volvo Forums - Volvo Enthusiasts Forum

Go Back  Volvo Forums - Volvo Enthusiasts Forum > Volvo Vehicles > Volvo C30
Reload this Page >

Brake lights coming on wiith park lights ??

Volvo C30 This compact hatchback gives a sporty feel without compromising versatility.

Brake lights coming on wiith park lights ??

  #1  
Old 06-30-2018, 02:40 PM
Junior Member
Thread Starter
Join Date: Mar 2014
Location: Durban, South Africa
Posts: 4
Default Brake lights coming on wiith park lights ??

Hi guys, my car is doing something very weird which I've only noticed today. When you switch the park lights on, the brake lights come on too. If you have the lights off and press the brake, it works like how it should but if you switch the headlights or even just the park lights on, the brake lights come on. What could be the problem? Please help. thank you in advance
 
  #2  
Old 07-14-2018, 04:14 AM
Junior Member
Thread Starter
Join Date: Mar 2014
Location: Durban, South Africa
Posts: 4
Default

Hi guys, just an update, connected the vehicle to an OBD reader (Delphi). Picked up a fault for the brake light switch, opened the switch and found that the contacts burnt, I have replaced the switch and the brake lights are still coming on with the park lights, and now the OBD reader is picking up "Comparison error". Didi anyone have the fault before and/or know how to fix this? Thank you
 
  #3  
Old 07-26-2018, 03:03 PM
Member
Join Date: Jul 2018
Posts: 87
Default

The question is: what burnt up the brake switch? To you pull a trailer or anything like that where you modify the wiring? Has the car been wrecked where wires could be pinched?
 
  #4  
Old 07-28-2018, 02:13 PM
Junior Member
Thread Starter
Join Date: Mar 2014
Location: Durban, South Africa
Posts: 4
Default

Nope, no trailer and no modifications to any wiring. The vehicle hasn't been in any accidents either
 
  #5  
Old 08-03-2018, 01:53 PM
Member
Join Date: Jul 2018
Posts: 87
Default

I'm not afraid to make an educated guess. Comparison circuits are used to tell if a light is burnt out. One side of the car is compared to the other. If they don't match, the check light comes on. Do you have a warning light for burnt out bulbs?

So: what could possibly connect two independent circuits? Obviously the brake lights are being energized by the tail light circuit. I wonder if there is a way that a defective light bulb could have shorted across the poles? Maybe an incorrect type bulb used?

There's always the possibility of wiring damage done by rodents. I don't know about South Africa, but here in the US, we have mice that nibble on wiring because the insulation tastes good to them.
 

Last edited by eflexter; 08-03-2018 at 03:59 PM.
  #6  
Old 08-08-2018, 06:28 PM
Senior Member
Join Date: Nov 2006
Location: Birmingham AL
Posts: 1,502
Default

I totally agree with the advice given by eflexter.
 
  #7  
Old 08-14-2018, 01:41 PM
Junior Member
Thread Starter
Join Date: Mar 2014
Location: Durban, South Africa
Posts: 4
Default

Hi guys, thank you so much for your replies. I did have a hunch about what was wrong but didn't want to say anything until I was completely sure. I did have the car checked out by a Volvo tech and he did confirm that the CEM is faulty but luckily in a way its only a fault with the brake lights.
 
  #8  
Old 08-15-2018, 05:37 PM
Member
Join Date: Jul 2018
Posts: 87
Default

That's interesting. Usually things STOP working when the CEM dies. Mental note for the future.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Reis Cinnic O'Neill
Volvo S70
1
03-11-2018 07:55 PM
wobotwalker
Volvo 240, 740 & 940
2
12-19-2013 05:37 PM
Bill Reichart
Volvo V70
2
01-24-2013 08:32 AM
miss ammo
Volvo 240, 740 & 940
3
04-01-2010 06:48 PM
chrystald423
Volvo V70
7
03-27-2010 09:05 AM


Thread Tools
Search this Thread
Quick Reply: Brake lights coming on wiith park lights ??


Advertising
Featured Sponsors
Vendor Directory

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.