Fuel Pump Relay R303 Replaced

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Kenerator

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Hi everyone,
I just replaced the fuel pump relay (R303) in my 2004 EB. Wanted to share my experience.

Symptoms - For about a year's time, the engine would occasionally stall out, or lose all power and run very rough. It didn't die very often, but if it did, it would restart right after. Then, it finally died and would not restart.

Based on reading the forums here I had suspected the fuel pump relay and had been meaning to check and replace if needed. The engine stopping forced me to jump in. Because the fuse box is pretty easy to remove, I skipped jumpering and testing, and went straight to removing the box. A quick inspection showed R303 partially melted and one solder connection fully degraded.
MltdRelayOnBoard.JPG
MeltedRelay.JPEG
DegradedConnection.JPG

New relay sourced from Amazon (Omron G8QN) for approx $6.00. I've read in several places that this is an upgraded replacement for the original Omron F8YF-BA relay.

I carefully unsoldered the bad relay being extra careful to not apply too much heat. I didn't want to damage the degraded solder pad any further. A solder sucker and solder wick was used to removed the old solder. Again, tried to be extra careful not to overheat the solder pad. I cleaned up the site and new relay with rubbing alcohol, applied a tiny bit of solder flux to the relay, inserted the new relay and soldered it to the board. The solder flowed out 100% on 3 pads and about 95% on the other two. I cleaned off any flux residue and put the box back together.

Here's a shot of the finished box. You can see the middle relay is different than the two above and below it.

Finished_Box.JPEG

This is not a difficult fix IF you are mildly proficient at soldering and have good soldering tools. This is a finesse job. Just take your time, pay attention, take pictures before and after disassembly. Check out this forum and YouTube for tips and tricks. You can do it!
 

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Kenerator

Kenerator

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Here is sort of an exploded view of all the box pieces while apart.

All_Pieces.JPG
 

Uncle Mike

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Very Instructive. Watched a you tube on removing. I wish it was more apparent if this was the issue, rather than the PCM.
 

Vincent Vega

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Hey thanks @Kenerator for posting this. I have 150k on my Exp and have not had issues yet, but I will follow your advice and will buy the solder sucker and wick. Still saves alot of money even after buying the right tools compared to buying a whole new fusebox, which I recently saw is something like $350-400.
 
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Kenerator

Kenerator

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Just completed my 2nd relay replacement on my buddy’s 2004 EB. His relay failed identically to mine. Thankfully installing the new one was uneventful. It’s a great feeling to turn the key and hear the engine start right up.
 

smartelbros

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Hey there everyone. I just did a fuel pump relay (R303) replacement on my 2003 expy. After reinstalling fuse box and connecting everything back up I went to turn key and my motor tried to turn over but doesn't seem like it's getting the right amount of fuel. It seems closer to being fixed then before I swapped the relay but I'm still not quite there. Any suggestions on what might still be the issue?

Thanks in advance for anyone able to help. I really need this thing to start up and run for me asap and I'm getting frustrated. I may be in over my head...
 
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