IPD sale XeMODeX - Experts in Volvo Electronics Free shipping all USA - Experts in Brakes
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy anything with this and it helps MVS!

Fuel Pump Relay Issues

Help, Advice and DIY Tutorials on Volvo's extremely popular car line -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

timothyj77
Posts: 4
Joined: Fri Oct 11, 2019 6:39 pm
Year and Model: 2000 V70 XC SE AWD
Location: Boise, ID
Has thanked: 4 times
Been thanked: 0
United States of America
timothyj77

Fuel Pump Relay Issues

Post by timothyj77 » Sun Jan 26, 2020 6:04 pm

I have a 2000 V70 XC SE (128K) and I'm on my fourth fuel pump relay in the last 14 months. Is there a known issue that could be causing this? My mechanic can't figure it out. Thanks!

User avatar
erikv11
Posts: 9597
Joined: Sat Jul 25, 2009 2:03 pm
Year and Model: 850, S/V70, 06 S60R
Location: Iowa
Has thanked: 91 times
Been thanked: 264 times
United States of America
erikv11

Re: Fuel Pump Relay Issues

Post by erikv11 » Sun Jan 26, 2020 7:17 pm

If you are buying aftermarket relays, for example made by KAE, that would definitely be a known issue. I wouldn't expect it to be as bad as three failures in 14 months but would still believe it.

If so, time to shell out for a Volvo relay. Even a junkyard relay is better than a new KAE one, in my experience. I'd probably try the latter and see if they keep dying, if not then shell out for a Volvo one.
These users thanked the author erikv11 for the post:
timothyj77
'95 854 T5-R, Motronic 4.4, 185k
'96 855 NA, 145k
'98 S70 NA, 220k (living out west)
'98 V70, T5 tune-injectors-turbo, LPT engine, 285k
'06 S60 R, 165k
'99 Camry V6 :shock: 125k
gone: '96 NA 850 210k, '98 NA V70 182k

timothyj77
Posts: 4
Joined: Fri Oct 11, 2019 6:39 pm
Year and Model: 2000 V70 XC SE AWD
Location: Boise, ID
Has thanked: 4 times
Been thanked: 0
United States of America
timothyj77

Re: Fuel Pump Relay Issues

Post by timothyj77 » Sun Jan 26, 2020 7:49 pm

I agree - but the last two have been Volvo relays. I'm stumped.

User avatar
abscate
MVS Moderator
Posts: 20557
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 290 times
Been thanked: 907 times
Trinidad & Tobago
abscate

Re: Fuel Pump Relay Issues

Post by abscate » Sun Jan 26, 2020 8:13 pm

Test current draw on the fuel pump.

Failure mode of the relays would also indicate failure root cause
These users thanked the author abscate for the post:
timothyj77
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW
Link to Maintenance record thread
Link To Volvo Glossary

mecheng
Posts: 1207
Joined: Thu Mar 27, 2014 7:49 pm
Year and Model: 1998 Volvo S70 T5
Location: Ontario, Canada
Has thanked: 3 times
Been thanked: 13 times
Canada
mecheng

Re: Fuel Pump Relay Issues

Post by mecheng » Mon Jan 27, 2020 9:23 am

How is it failing? I know the common failure point, is the solder joint.

Open one up and have a look at the coil, activate it with 12V, even a 9V batter, does the spring move. If it does test the continuity and try to see if you can peak a look at the contacts.
1998 Volvo S70 T5 - SE - 240km - Sold July 2018
1997 Volvo 850 GLT - 190km
Boost is my drug of choice

ToriWhite
Posts: 92
Joined: Thu Sep 15, 2016 11:00 pm
Year and Model: 1996 850
Location: Davis
Has thanked: 15 times
Been thanked: 3 times
United States of America
ToriWhite

Re: Fuel Pump Relay Issues

Post by ToriWhite » Mon Jan 27, 2020 3:19 pm

I know a bad relay can cause a bad pump - so whenever your pump goes, swap the relay too to be safe.. I wonder if a bad pump can kill a relay? I wouldn't be suprised

User avatar
BEJinFbk
Posts: 3697
Joined: Sat Jan 05, 2008 10:32 pm
Year and Model: '98 V70 R
Location: Fairbanks, Alaska
Has thanked: 23 times
Been thanked: 44 times
United States of America
BEJinFbk

Re: Fuel Pump Relay Issues

Post by BEJinFbk » Mon Jan 27, 2020 8:01 pm

ToriWhite wrote:
Mon Jan 27, 2020 3:19 pm
I know a bad relay can cause a bad pump - so whenever your pump goes, swap the relay too to be safe.. I wonder if a bad pump can kill a relay? I wouldn't be suprised
I'm not sure that I understand your logic.

The relay is just a switch that turns the
pump power on and off when the ECC
tells it to. Maybe if the contacts were to
stick and the pump relay continued to
run, there might be a problem. But it
would have to run a loooong time.

Conversely, a bad pump that draws too much
current is much more likely to damage the relay.
And the main fuel system relay will cut that power
when you turn off the key anyway, so it's not going
to runaway when the car is shut off.

As far as swapping the relay just because you
dropped in a fresh pump, I'd bank that cash.
If it ain't broke... Just Sayin'. ;)
'98 V70 R - Well Equipped for Life Up North... ;)

ToriWhite
Posts: 92
Joined: Thu Sep 15, 2016 11:00 pm
Year and Model: 1996 850
Location: Davis
Has thanked: 15 times
Been thanked: 3 times
United States of America
ToriWhite

Re: Fuel Pump Relay Issues

Post by ToriWhite » Wed Jan 29, 2020 4:38 pm

BEJinFbk wrote:
Mon Jan 27, 2020 8:01 pm

...stick and the pump relay continued to run, there might be a problem. But it would have to run a loooong time.
Don't quote me on this, but I remember reading somewhere that a frequent point of failure for pumps is a faulty relay that, for some reason, malfunctions to where it 'flickers' on and off, and that behavior hurts the pump. Of course, if you've got a multimeter and the know-how, you don't have to run off of heresay lol

Post Reply
  • Similar Topics
    Replies
    Views
    Last post