P80 Fuel Pump Relay Repair master thread 9434138 9434225 Topic is solved

[shiloh51933]

Shiloh, a capacitor is not a fuse; it is not designed to fail. The voltage rating does not specify its behavior, but only the maximum voltage under which it can be counted on to display its rated capacitance. You just have to be sure the rated voltage is above the voltage it will actually see.

Understood. I'm still learning about automotive electric/electronics(1st year student of 2year Auto Associates Degree), regardless of the 15 years plus turning wrenches this area has always been below par. Thanks.

[goldfish]

I just had two instances out of the blue with the stalling yesterday and not starting up right away. Drove it to work and back today and it ran fine. I found this post on the forum and the symptoms sound the same. I pulled the relay, it is the 89 8797 000 and I can answer your question; yes, the capacitors are the same values. Judging from your pictures they seem to be identical with the exception of the surface mount IC. Even the 034 LL etched on the board is the same, so I think would be safe to assume it's probably the same board. I just finished the capacitor replacement and it seems to be running fine so far.

[goldfish]

Running fine today. Had one of the electronics guys at work take a look at the capacitors. The 100uF was pretty much completely dead, the 22uF was still functioning, but only at about 80% capacity. Right now I'm pretty confident this was the right fix in the situation. I used caps rated up to 105 celcius so they should last as long as the originals. My relay had a date of 1994 on it, so 15 odd years seems a reasonable amount of time. I'm going to hit up the wreckers this weekend and see how many relays I can round up and fix, maybe make them available to people on ebay or something.

[ockids]

It's a great post. I'd like to examine/repair my relay on 2001 XC70. The trouble is, I cannot lift the fuse box after undoing 4 screws. I also released 2 latches holding the front side of the fuse panel. But its back side (closer to the firewall) does not move at all as if something is holding it down. Any suggestions?

[ockids]

Sorry for the typo. I want to repair my relay, not replay
Any suggestions how can I lift that fuse panel in 2001 XC70 to get to the relay?

[ockids]

Another update. I got in there. There are no relays under the fuse panel in my 2001 XC70.
Does anyone know where is it located and it's number and leads?

[ockids]

Folks, I found it. Thanks to http://www.v70xc.com/resources/how-to/p ... cation.pdf . It is listed on page 6 as CMI12. It is located in the passenger compartment behind the dash board a little below and to the left of the steering wheel.
I had a hard time to get my 2 hands there, and decided not to attempt troubleshooting single handed. Will let a mechanic to do that, especially considering the relay is only one of several suspects for my engine not running. It can be the fuel pump or a damaged hose, etc. as described by others in this forum.

[ambishop]

Just as an update. I have been looking over my relay to determine if this is something within my solder abilities, and wanted to post some observations.

the 22µF capacitor 25V 105 degrees C. Your radioshack lists 35V 85c
The 100µF capacitor is 16V and the radioshack lists 35v 85c

The ones I found there were closer matches were as follows:

https://secure.vividcluster.crox.net.au/jaycar2005/productView.asp?ID=RE6310&keywords=100uf&form=KEYWORD

and

https://secure.vividcluster.crox.net.au/jaycar2005/productView.asp?ID=RE6079&keywords=22uf&form=KEYWORD

[cn90]

Re: Green 9434138 vs Red 9434225

Any fuel relay guru?

I understand that the original thread by Ozark Lee is on the mechanical-type relay Green 9434138.

I have a specific question: I have the "later-type" Fuel Relay Red 9434225...is this (Red Relay) still prone to failure as the early version of Green 9434138?

The Fuel Relay Red 9434225 inside anatomy was posted by "confused al" here:
https://www.matthewsvolvosite.com/forums ... 071#p75079

[tappolon]

What other symptoms are seen if the fuel pump relay is causing the vehicle to not start?
Will it prevent the ECU from activating the electric distribution system? I just want to check if the fuel pump relay is a likely cause before ordering and waiting for a fuel pump relay, or trying to repair the relay circuit without having any soldering tools yet.

My '97 850 (base) will crank, but won't start. The starter was just replaced because the car wouldn't even crank and the starter didn't activate when direct power was applied from battery. Now it will crank, but won't start. There is no fuel pump noise, no fuel pressure, and no spark. Basically, it seems like the ECU isn't doing anything. Would replacing the ECU make more sense than the fuel pump relay? The ECU is actually cheaper used from a salvage yard ($30) than getting a new relay online ($40-$115).

I guess I should try jumping the 15 and 87 pin positions in the relay socket first, but that previous post about it starting to smoke afterward has me a little worried (though apparently that still worked for him).

Thanks