2006 V70 brake Vacuum pump/switch 31317445 31265825 Topic is solved

[astouffer]

So what is the solution in my case? Is this a symptom of a larger problem or something these cars have always done? I'm the third owner and the guy I bought it from said its been like that the entire time he owned it.

[IMSITTINGINYOURCHAIR]

Hmm, so that's why I haven't really had boost assisted brakes...

it's been like this since I brought it home. never looked into the issue. Not fixing it though. Great write up though. would've followed it If I would've ever gotten around to the issue.

[udogu]

Excellent write-up. I just did this on my '07 XC70, and everything (including part numbers) is the same. One thing I did differently -- on step 5, you can see in the picture that the bracket that the air box attaches to has U-shaped slots where the left two clips attach. This means you can save a lot of yanking on the air box. Pull out the clip on the right side and then just slide the air box to the left to remove it. It slides back in easily when replacing it.

[Rgrigsby]

My check engine light recently came on in my '06 S40. I've had the brake problem described above since last winter. The dealership said that the vacuum pump and switch failed, resulting in power being drawn from the engine (hence the check engine light). I'd like to fix this myself rather than paying the $650 Volvo would like to charge. However, I can't seem to find a switch. Does the '06 s40 have one? Or by switch did the dealership mean sensor or something else?

[dan777]

I don't think the engine light comes on because of the vac pump. Could be an additional problem...

[jimmy57]

If the vac pump blows the fuse that kills the oxygen sensor heater power and sets DTC(s) on P1 platform models.

[Rgrigsby]

Thanks for the responses. The error message from is ECM-250a (Long Term Trim - Upper Limit). I think this can be associated with a vacuum leak or blown 02 sensor fuse (as stated above). Does anyone know how to check this fuse? Where can I find it?

Also, from my initial post, I asked about the '06 S40 not having a sensor on the vacuum pump. I think I've discovered that the sensor comes as part of the vacuum hose (Product # 31201430). At least, this is what they tried to sell me when I called the volvo dealership asking for a vacuum sensor.

Thanks again for your responses. You'll have to forgive me for being such a novice. I'm trying to learn to do as much as I can on my own.

[yorkiemomaws]

I just replaced the vac switch tonight. My brakes actually worked fantastic with the old switch but it was broken & the spring was hanging out of the switch. I changed it with the battery disconnected but put everything back exactly as it had been. The fuse is fine. However, I drive with hand controls & now I cannot push the brake. My husband came out to the car & tried to use the brakes with the foot pedal. He could barely get the car to stop in drive or reverse, either.
Any ideas what in the world is wrong?

[dan777]

If the brake pedal feels very hard but it doesnt brake that is an indication of no vacuum. Does this happen only when the engine is cold or all the time?
Maybe the vac hose is not connected...the vac switch activates the vac pump only when the engine is cold and is not enough vac pressure in the system.

[Kix]

Thank you for a fantastic write up, you saved me a lot of money.

I've installed a new switch and pump.

Now when I switch the car on (not starting) I can hear the pump from inside the car for about 2 seconds. Still without starting the car the pump kicks in if I press on the brake pedal and comes on again if I release the brake pedal. Is that normal? Also is it normal to hear the pump from the inside of the car?

I don't want to do anything to hurt the pump as it was hellishly expensive here in South Africa.