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

Post by **abscate** » 09 Nov 2018, 20:14

My 2005 NA has the brake booster pump.

Post by **jimmy57** » 09 Nov 2018, 20:15

all s40/v40 2000-2004 had them. 4 cylinder engines have too low vacuum idling, a/c on, in gear, and cooling fan running for brake booster.
The others starting 2002 got them.
Dual cvvt engines have very little intake vacuum when started cold due to the radical cam phasing and retarded ignition timing, both for catalyst and engine warm up speed. CVVT on either or both cams is utilized for quicker warm up and hotter initial exhaust temps. All can have marginally low vacuum when cold to support brake booster for easy pedal.

zanzabar · Post by **zanzabar** » 12 Nov 2018, 14:23

On my 2007 2.5T I thought I had a vacuum pump/switch problem, since recently on 2-3 occasions when starting from cold, AC on I think (warm outside if I recall correctly) and driving away quickly, reverse first to turn around, then drive. I had a stiff brake pedal and almost no braking. It always resolved itself in ~15 seconds. This first happened about 6 months ago. Then I found this thread and ordered a new switch and pump and went to put them in yesterday.

Digging into it what did I find? The dang pump plug was disconnected! The pump hadn't been running at all for several months or more. Braking has always been mostly fine.

Interesting that there is no error code thrown for not having the vacuum pump plugged in.

So, now I have a brand new pump and switch out of the original packaging. I'll sell cheap to anyone interested, PM me.

Post by **oragex** » 13 Nov 2018, 00:43

There is a chance the previous owner disconnected the pump because it was running too much. This happens when the booster seal at the pedal fails and starts leaking. I have 1-2 videos on youtube on the subject.

Post by **abscate** » 13 Nov 2018, 02:11

Bump for book keeping and parts numbers

Excellent thread with pics and diagnostic skills!

zanzabar · Post by **zanzabar** » 13 Nov 2018, 12:11

oragex wrote: ↑13 Nov 2018, 00:43 There is a chance the previous owner disconnected the pump because it was running too much. This happens when the booster seal at the pedal fails and starts leaking. I have 1-2 videos on youtube on the subject.

Good point! I already bought the grease, I'll go inspect and lubricate that seal asap.

Post by **erikv11** » 13 Nov 2018, 13:33

This thread and the videos from oragex really helped for troubleshooting when my 06 S60 turbo had the same problem.

I fixed it with a booster pump from the junkyard, scavenged from an 08 V50: viewtopic.php?f=9&t=85448

pdr1966sc · Post by **pdr1966sc** » 02 Dec 2018, 20:08

Schematic of this?
I am having a brain cramp here -
The orange connector shows 12v - key on - on one pin.
When the Vac switch is electrically closed, the 12v is then fed to the Vac Motor - but I only see one wire (harness of 2) going into the motor.
There must be a little more to this good thread than is shown??
On my car the 12v hot is on the orange connector with key on, but shorting across the orange connector did not result in the pump running (and it is very likely it is worn out...anyways) as I am trudging through a 'new to me' car.
Does anybody have a wring diagram, atleast this is all easily accessible so I may just pull the pump and bench test/dissassemble.

Post by **erikv11** » 04 Dec 2018, 08:04

Sounds like a dead pump, if you're not getting the info you need from the first page of this thread (sorry I did not review it just now to sort out your comments

) then I would just pull the pump, removal is super easy. Test the pump on the bench with 12V.

- To release the vac line on the brake vacuum pump, press on the green connector tab while pulling the hose off the pump nipple.

- To remove the pump, unhook the bracket (2 bolts, they use a 10 mm socket) and drop the pump down while still attached to the bracket.

- To reinstall the hose, just push it on until it clicks.

Rvolvos · Post by **Rvolvos** » 15 Dec 2018, 20:14

oragex wrote: ↑15 Jul 2018, 04:25 An updated video

Great video. I did watch Your previous one about lubricating the brake booster seal and ordered the PTFE/ silicon lube from EBay, because you’re mentioning being slightly thinner versus the Volvo lubricant
Do you still recommend using this, it will be delivered next week.
(Item Name: Lubricant TF - Grease Paste -Teflon grease - Ingredients: PTFE , silicone - 3,5g
Item# 263549953669)
Thanks much,

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

Re: No Brakes when cold - Vacuum pump/switch replacement w pics