2006 XC70 Cruise Control not working

fontoledo · Post by **fontoledo** » 05 Apr 2021, 21:40

Hi all

The cruise control in my 2006 XC70 has not worked since I bought it, but now that I'm putting together a few summer trips, I'd like to get it fixed. Controls on the steering wheel do seem to be properly connected and "semi-working": while pressing the Cruise button, the Cruise notification appears on the control panel. However, when attempting to set a speed, nothing happens: as soon as I release the gas pedal, the speed drops. I've tried several combinations with both the +/- speed buttons and the ones on top of it, but nothing works.

Any clues on where to start looking? Is it worth disassembling the steering wheel to check cable connections? Could it be mechanical?

Thanks in advance!

Post by **RickHaleParker** » 05 Apr 2021, 22:16

fontoledo wrote: ↑05 Apr 2021, 21:40 Any clues on where to start looking? Is it worth disassembling the steering wheel to check cable connections?

You need a diagnostic scan. There are several codes that will disable the Cruise until the problem is fixed and the code is cleared. The code for Brake pedal switch is just one of them. Are your brake lights working? Both brake pedal switches in the correct position?

fontoledo · Post by **fontoledo** » 05 Apr 2021, 22:29

Thanks for your answer!

-My brake lights are working fine.
-Not sure what the “brake pedal switch” is, though.

I can plug-in my FIXD tomorrow and see if there’s any Cruise Control related codes but not that I remember. Also, I’m not sure I know how to disable a Code; I only know how to read them. Would you mind elaborating a bit more?

Thanks

fontoledo · Post by **fontoledo** » 06 Apr 2021, 19:31

FIXD throws 0 codes, so no alerts from the computer at this point. Anyone, other thoughts?

Post by **RickHaleParker** » 07 Apr 2021, 05:24

fontoledo wrote: ↑06 Apr 2021, 19:31 FIXD throws 0 codes, so no alerts from the computer at this point. Anyone, other thoughts?

FIXD is not much of a scanner. It is trailing edge technology. Something a MBA would cook up not a EE.

"Currently, FIXD is able to read active check engine light. The other lights such as TPMS, ABS, Airbag, Maintenance lights, and Stability Control, are controlled by manufacturer-specific parameter identifiers, which make it difficult to communicate through the OBD-II port. We are currently working on licensing that information from the manufacturers."

Stonedraider88 · Post by **Stonedraider88** » 07 Apr 2021, 08:13

I'd check again what Rick said. Can quite possibly be the brake pedal switch. I think its under the actual brake pedal itself, and from what I read, is an absolute pain to get to. I wouldn't take out the cruise control module itself just yet, as there is literally not much that can go wrong with it, regarding a loose connection. Can also be a faulty module. That was my case, however replacing it it really simple.

Post by **RickHaleParker** » 07 Apr 2021, 14:19

Stonedraider88 wrote: ↑07 Apr 2021, 08:13 I'd check again what Rick said. Can quite possibly be the brake pedal switch.

There are two brake pedal switches one for Brake lights and one for Cruise control. These can move in the bracket. When they do the switch is open all the time. Fooling the CEM into thinking the brake pedal is depressed all the time. Be like riding the brake and trying to set the cruise control.

Post by **firstv70volvo** » 07 Apr 2021, 15:32

fontoledo wrote: ↑05 Apr 2021, 21:40 Hi all

The cruise control in my 2006 XC70 has not worked since I bought it, but now that I'm putting together a few summer trips, I'd like to get it fixed. Controls on the steering wheel do seem to be properly connected and "semi-working": while pressing the Cruise button, the Cruise notification appears on the control panel. However, when attempting to set a speed, nothing happens: as soon as I release the gas pedal, the speed drops. I've tried several combinations with both the +/- speed buttons and the ones on top of it, but nothing works.

Any clues on where to start looking? Is it worth disassembling the steering wheel to check cable connections? Could it be mechanical?

Thanks in advance!

My cruise control stopped working and it was the brake pedal position sensor. This sensor is next to the master cylinder and held in the brake booster with a round clip. It's a sliding type contact with a rod in the brake booster and two fingers internally that contact and slide across strips connected to resistors on a small circuit board. In my case there was a solder joint that broke internally. These switches can be opened up and repaired but it might be safer to just replace the switch if that's what's causing the problem. These simple sensors are not cheap so a salvage yard may be your friend.

My symptoms were different though, I did have a code and I wasn't able to turn on cruise control with the cruise button. I can't recall the code number but it had to do with the brake position sensor and I read the code with a BSR PPC diag reader. I attached some photos from a person that repaired this switch, couldn't find the original link though.
I don't know if this brake position sensor is what's causing your cruise control problem but did want to mention this is a part that could potentially cause the problem.

fontoledo · Post by **fontoledo** » 12 Apr 2021, 10:18

Thanks for you replies!

@firstv70volvo is this https://www.fcpeuro.com/products/volvo- ... 06#fitment the piece you're suggesting I might need to change? I want to make sure I get it right before looking for the salvage option. Thanks!

Post by **firstv70volvo** » 12 Apr 2021, 11:54

fontoledo wrote: ↑12 Apr 2021, 10:18 Thanks for you replies!

@firstv70volvo is this https://www.fcpeuro.com/products/volvo- ... 06#fitment the piece you're suggesting I might need to change? I want to make sure I get it right before looking for the salvage option. Thanks!

Yes, that's the brake pedal position sensor. It does looks there's been a change in the connector location between 2001 / 2002 model years so there may be a difference in the connector too, match what's on your car now. As I mentioned I don't know if this part is causing your cruise control problem but it is a part (if bad) will prevent your cruise control from working.