The infamous 15528707 fuel pump relay.

[DaveVA78Chieftain]

The other relay should be the emissions relay for the pumps.

Nope, that's the magnetic contactor relay for the starter circuit.  Used to ensure enough current is supplied to the starter.  Unique to the P30 platform.  Was part of the slow starter solution when the engine is hot.  You see it in the P30 wiring diagrams.

[ClydesdaleKevin]

Thanks Dave!!!

Kev

[CapnDirk]

Found one that is NOS.

Do you have the old one?

[tmsnyder]

Yes my original is still working in the RV, I just picked up one to have as a backup. 

[CapnDirk]

Ok,  If they had any more, let the people here know, I'm sure we'd buy them.

[CapnDirk]

High M&J.  That's the retrofit for using an of the shelf headlight or something similar relay.  IT would require surgery on the OEM plug, and no primer/delay circuit.  The one I have has components (transistor, resistors, maybe a diode or two.

[EldoradoBill]

As stated earlier, there are vendors who can repair or rebuild what you have. My guess as to why no one has reverse engineered a replacement? Low to no demand...


Bill

[tmsnyder]

until you're dead on the side of the road, then there's a serious demand 

[CapnDirk]

Good point tmsnyder.  We usually don't replace what's not broke.  And the side of the road is where it breaks.


If everyone will look back, my intent with this thread was just to point out what I found, and a fix.  I don't know how many of us take a soldering pencil with us with the rest of our tools, but if you found the same thing as I did on mine, you could fix it on the side of the road.  Hence the statement that the post was a sead.


The failure on my relay was not a component, or mechanical failure but rather a weak part of the design.  If the primary reason for it's failure was what you saw at he beginning of this thread, then there may be no need for a replacement.  Just do what I did.


I would be curious to see the inside of someones still running OEM relay to see if it is showing any signs of failure in the same place from heat.

[ClydesdaleKevin]

I still have my old one.  If I come across it again I'll open it up and take pictures to see if had the same damage as yours.

Kev

[CapnDirk]

Refresh my memory Kev.  Was the old one not working?


If so, we would like to see the inside, or have you send it to one of us for examination, repair.


They were prone to failure, but I'm trying to determine if this was the common failure meaning anyone would be able to repair theirs rather than be stranded somewhere and have to chop up wiring to splice in something else.


Thanks for your input.

[eightball]

Nice find and fix!

Greetings all, well being a new be here I will mention about the rig we are now restoring, it is a 1990 Holiday Rambler AlumaLite XL 27' Class A Motorhome, and we have the here mentioned problem of no fuel coming to the TBI injection. First I notice we don't have the hybrid part time fuel prime set up,  as we do not have the mechanical fuel pump but an electric in-tank full time fuel pump. Last year the fuel system was working fine, but after another year in storage when we first went to start the engine it did not fire. After looking all over the web none of the places have shown us where the fuel pump relay is located, nothing on the firewall, fuse panel or motor housing area show any signs of said relay ether. So for as an emergency fix we have hooked a fuel line from the AC power generator electric fuel pump to the TBI injection fuel inlet.   

Now awaiting delivery of two new electric external fuel pumps we will install later, but we do want to find the fuel pump relay location, after seeing this article about the "The infamous 15528707 fuel pump relay" I think it may be the cause of our problem with our in tank pump. However not finding a fuel pump relay and not hearing any click sound when turning on the ignition it would be nice to locate said relay to see if it has the open circuit problem, by the way that could have been prevented if the makers of the relay had of added more solder to the printed circuit board, a simple drop more would have made this devise to loose its fame by a rather large margin. Thank you all... EB

[Rickf1985]

The fact that you have fuel injection you will not have that relay. You fuel pump will be controlled from the ECM through the OBDI system. The relay should be in the fuse box along with the other relays like the fan relay. I am not familiar with the setup in your RV but in a pick-up this box would be under the hood and apart from the standard fuse box in the passenger compartment.


On edit, I just looked at my 1990 service manual and you should have a carburetor on that RV. A 90 is usually built on an 89 year chassis. Unless you have a really late model coach on a early 90 model chassis. I have a 1990 Pace Arrow and it is carburetted.

[eightball]

Thank you for a rapid response, I have been surfing the web and perhaps ours is a 1990 mfg built motor home that is a 1991 model. If like in the automotive business many vehicles were built a year earlier than sold. I believe the TBI was used in the 1991 Holiday Rambler AlumaLite XL 27' Class A. There seems to be so much confusion on the web lol...

[EldoradoBill]

The P30 chassis serial number is affixed to the front of the radiator support drivers side. Use this to determine the year, not generalizations. My 91 Winnebago was built November 90 on a 91 GMC chassis.


Bill

[DaveVA78Chieftain]

To the best of my knowledge which is also supported by the 1990 & 1992 wiring diagrams, a fuel pump relay is still used.  Like in previous years, the relay is still located on the left side engine cover (engine side).  For 1990, a Oil Pressure safety switch is also in the circuit.  The Oil Pressure safety switch is not reflected on the 1992 wiring diagrams; relay is controlled by ECM

[Rickf1985]

And Dave corrects me again. He just LOVES doing that. :)rotflmao :)rotflmao :)rotflmao  I don't mind, better a proper answer than a guess. Like I said, I knew on the cars and trucks it was in the relay box under the hood, on RV's........... all bets off. I did NOT know they still used that garbage relay though.

[DaveVA78Chieftain]

I am not sure if it is the 15528707 relay for TBI.  All I said was "a relay" is still used that is located the same place as previous years based on the wiring diagrams.  Starting in 1990, the 11x17 wiring diagrams not only contain schematics, they also show component locations.

[eightball]

Hey just want to thank you all for your responses, I have used them to search out and find va vin numbers that I have a 1991 Aluma-LiteXL seems after many years of storage from where we bought the rig it had a lot of varnish in the TBI injectors, I found while going through the TBI carburator that the injectors will clog early on. I used a 12 ac transformer to buzz (not for long periods of time it will heat up) that they will free up. You can actually do this with the TBI still mounted on the engine, you will hear them buzz when they are working freely. Knowing I will need to drop the gas tank to replace the fuel pump and clean the tank, for now I needed to to move the rig to another location. At first I used the old stick propane hose over the TBI throtel plate and fire engine to see what works. Then the old electric gas pump from 5 gal tank of gas inlet, the pump is a 7 - psi but the engine fires and is able to be moved. As for fuel relay nothing found but this being injection the ECM  electronic system, fuel fuse stays hot so I assume fuel pump is stalled from gum varnish. Again thanks for all your efforts, all I can say is keep googling until what your looking into makes sense, and look out for youtube posts so many are way out there lol... But still learning more about it...

[DVan]

Ran across this while researching this topic:


https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28535405.cfm


It supposedly is a relay that can substitute for the 15528707 with some pin-out mods.

[Fleetwoodfred]

Hello all,
I found this forum from googling, trying to fix my RV. It was the infamous relay. From what I understand they donââ,¬â,,¢t make it anymore but someone posted a link to a replacement that was the same thing, Airtex 1R1240 from ââ,¬Å"Same day auto partsââ,¬Â in CA. It is an exact replacement, it fixed my problem, saved me a bunch of money and I can get from AZ to Missouri with my two dogs and beat the heat.
So I just want to thank you good folks!

[thomas]

HI! saw the post for relay!  I bought that one and swapped it for the 707 and no good!! didnt get pump to run!! did you do anything special??  I just got 2 of the older 707 relays today in phx.az.! will try tomorrow!

[Rickf1985]

Thomas, Have you checked the oil pressure safety switch to see if it is working? Or if it is even hooked up? And made sure you were getting power to the relay on the proper wire? And that the relay is grounded? Seems to me that with all the relays you have tried there is a wiring issue and not a relay issue.

[thomas]

HI RICK!! glad you saw my post!!  YES! the oil switch works, got power,and i jumped it with a paper clip! IVE got 2 good relays,they are both like new inside,and i did not see that flaw in the solder that was talked about way back ! I know im gettig power to the relay,i checked it last time,by test lite  on the pins on the plug and! i have not yet this time,  all the wier is in good shape! O K now I dont find a fuse for the fuel pump! RV only has a tiny little fuse box! should it have one?? NOW back last month or so, I had the new pump in the tank run for a test! but I dont re member how I did that! how i jumped it, I just remember it pumped so gas when i tested it,, cause I was realy worried earlyer that I had fogoten to connect the pump inside the tank,BUT its OK it will pump,   just dont remember what I did.  I did not hear or feel anything with the new relays when I turned the key! should it buzz??  THE old relay was completly rusted inside,it got water inside! I thinh it has been like that for a long,long time. can you tell me how to test this out with my test blite??  CALL ME  520 205 1737 !!

[thomas]

ALSO!! I tried a new # 1r1240 relay like the other guy did  no good!  and  FYI  I have the 4barel carb no tbi,I ask him in a post how he got the 1r1240 to work