2002 Honda Odyssey - Still no start after replacing fuel pump..? Check Main Relay!

Рет қаралды 24,776

2 жыл бұрын

Customer's van was stalling. Went to another shop and they put in a fuel pump. Not knockin that because they couldn't get it to act up. So a fuel pump was reasonable. Customer went back to that shop a few times after because it was still stalling. After the van sat for a bit it would usually start. Might stay running for a while or might only last 5 minutes then stall. Fuel pumps typically do not fail like this...
Customer then comes to us wanting us to put in their warranty fuel pump. Luckily for me, I was able to have it be a no start long enough for me to do my testing. In this video I go through the full testing of the Main Relay. Verifying everything it would need to function properly and also how to bypass it.
These Main Relay's are notorious for cracked solder joints and sure enough that's all this problem was. If I were to add solder to that joint then this vehicle would start and run. This might be something to consider for your own vehicle but as a business that is liable... we're putting in a new part. You don't want to have something else fail in 3 months while they're on vacation then you're on the hook for the tow bill as well! Nobody wins. So we fix it right the first time.
If you've got a Honda of this generation then drop a comment to let us know if you've had to change your Main Relay!

Пікірлер: 28

@rich5034 Жыл бұрын

Great video brother. Watched your video start to finish, printed up a wiring diagram to compare and it matched my 2004. Borrowed a few sewing pins from the wife to make a quick test jumper. While cranking as you did, I bridged the white/green to the Black and Yellow (shoutout to Wiz Khalifa) and it started right up. Disconnected jumper and replaced relay with aftermarket from local parts supplier. Needed it fixed asap so paid a bit more but you can find them online for around 40$ next day. Thanks again.

@eurbanautotech Жыл бұрын

@Rich Thanks for watching! Glad you got yours figured! These were pretty common failures. Especially in the 90s. It was almost to the point that you could just throw a main relay at the car whenever you'd get a stall/no start when warm. But they make for great case studies/learning experiences for electrical testing. They're pretty easy to get to and pretty simple to test. Sewing pins aren't the only things that are useful! The best tool for opening up a wiring harness is a sewing seam ripper. Snap-on even makes one! Of course they can't call it a seam ripper... they gotta call it a ... "Soft Grip Terminal Tool" shop.snapon.com/product/Soft-Grip-Terminal-Tools/Soft-Grip-Terminal-Tool/SGTT4B

@wescrews9253 Жыл бұрын

I had this same issue on a 2004 Odyssey. I found that the fuel pump had lost its ground. The broke wire was below the floorboard and above the fuel tank. I opted to bypass the broken ground wire and substitute another. Made the repair and van started.

@Mimibear1 3 ай бұрын

Thank you finally found someone that’s knows what there talking about I’ve been looking for the same problem as my 02 and man I pulled the relay and fixed it it was cracked like you said I will update if it’s works out

@stevetilbrook3402 8 ай бұрын

To check the voltage you turn the key all the way on and listen over your shoulder for the fuel pump to prime up it'll whirr, for a second or two. if its not priming the first culprit is a relay under the drivers side dash. the pump is in the fuel tank under the floor behind the spare tire . I pulled the relay and re soldered the connections on the back and it worked. saved $50.

@theboogerbeater Ай бұрын

I did the same thing and it worked. Thank you for the insight

@donaldgianoli431 2 ай бұрын

Very educational, thanks.

@nickotasla3091 4 ай бұрын

👍Learned so much from you Teacher. Really appreciate your channel. GOD bless you.

@tjwithanak7517 8 ай бұрын

Thanks! Saved me 100 bucks. It was a tough item to find at pull a part. Common issue I guess. But we found one!

@eurbanautotech 8 ай бұрын

@tjwithanak7517 Thanks! Glad I could be of help and save ya a headache! Good thing you were able to find one. These are the kinds of things that go wrong all the time so you go to your local salvage yard only to find someone has yanked them out of every car there!

@faroukkhan6777 9 ай бұрын

Thanks excellent for ur time and information 👌 I've got my Honda jazz no start , green key light flashes,,

@eurbanautotech 9 ай бұрын

@faroukkhan6777 Glad you found it helpful! What year is your Jazz? Green key means there's a problem with the security system. Usually it's the chip inside the key has gone faulty. Do you have a spare key you can try?

@faroukkhan6777 9 ай бұрын

Good morning thanks ,,no I must have one made , Jazz is 2006 , 1.3 ,, when I take plug off from EGR unit,, green light off,,???any thoughts on that, thanks have a great day 👌

@nilolee2426 Жыл бұрын

Wow, good job! nice knowing about this issue. I do have have a 2004 odyssey ,I’ll keep in mind about this relay in the future. But I don’t have the wiring diagram that you used

@eurbanautotech Жыл бұрын

@Nilo Lee Thanks! It is a pretty common problem on 90s to mid 2000s Hondas. Usually the sorta thing where the vehicle will start cold and then stumble and stall once it warms up. Then it won't start again until it cools off. After a while it'll just not start at all. We have Alldata at the shop. It can be hard to get good diagrams if you're on your own. Alldata/Prodemand cost quite a bit. You can get DIY subscriptions just for your vehicle. I don't know how much they cost but I imagine they're pretty reasonable.

@nilolee2426 Жыл бұрын

@@eurbanautotech I heard that solder connection goes bad in the relay. I’ll check mine in the summer, thanks for the video

@willferrmail 10 ай бұрын

Thanks!

@eurbanautotech 10 ай бұрын

@willferrmail Thank you so much! Hopefully it was able to help you out some or provide some entertainment. I love being able to pass on all the neat and quirky things I see along the way!

@minervar3890 Жыл бұрын

Hello, my “04 odyssey sounds exactly like the one on the video. We replaced the main relay and will not start still. Any recommendations?

@FilmFactry Жыл бұрын

My Mothers 07 had 2 intermittent engine turned of driving in a parking lot. No issue restarting. I checked the battery and the Alternator is new. There was no CEL either time. And I checked for codes and nothing. If the Main relay went off would it throw a code? Thanks!

@eurbanautotech Жыл бұрын

@FilmFactry There are no codes when the main relay goes. From what you're describing I would probably guess that it's not the main relay. The problems that come from the main relay are usually due to bad solder joints. Typically what happens is it's fine when it's cold. Then after it warms up the bad solder joints break open and you lose fuel pump. It usually won't start again until it cools back down. From what your describing could be something like a failing cam or crank sensor. Hopefully you'll get a code soon. Sometimes these intermittent issues that don't throw codes can be awful to try and track down! Good luck!

@theboogerbeater Ай бұрын

Thank you , what was this part called?

@zulemabarajas9131 Жыл бұрын

i cant find it on a odyssey 05😢

@denisouncho2513 10 ай бұрын

me too😢

@Void_777 10 ай бұрын

I swapped the main relay & bought a new fuel pump, still not power to the fuel pump with new relay main, now why is that, what else could it possibly be? I know the relay & pumps work with external power from a 12v battery, but not with the harness for power from the relay, I've checked all fuses & wires have power, 2002 honda odyssey, if anyone has any ideas, please let me know.

@eurbanautotech 10 ай бұрын

@Void_777 Hmm... Makes me wonder if the main relay is even being turned on? When you go to start the vehicle does the green key symbol on the dash go out? If it stays on then you have an immobilizer issue. You could try manually powering the fuel pump wire coming out of the main relay. It's the big black with yellow stripe wire. kzfaq.info/get/bejne/ZtqCfrOqzZ7doX0.htmlsi=ZMWqI3Jhxm9hhqSE&t=1102 If you jumper power there right after the main relay but you still don't have power at the fuel pump then you know you have a break in the wire somewhere between the main relay and the fuel pump. If it does start then you either have a problem with your new main relay or it's not being triggered. The PCM activates the main relay by supplying a ground to pin #1. The smaller green with yellow stripe wire. So if you supplied ground there and got power to the fuel pump then you'd know your wiring, fuses and main relay were good. Then you'd be looking at something like an immobilizer, ignition switch, or PCM issue. Good luck and let me know what you find out!

@Void_777 10 ай бұрын

@@eurbanautotech I figured it out bro, it's the small wiring harness that runs in under the floorboard & connects to the fuel pump, it's melted and corroded from being exposed to moisture/rain, $15 to replace it, I appreciate you taking the time to reply to me, anyways it's the small 4 pin to 5 pin connector, thanks for your time & consideration, God bless.🤝🙏

@eurbanautotech 10 ай бұрын

@Void_777 Awesome find! Damaged wires in places like that can sometimes be really unpleasant to locate. Plus repairing the actual damaged wire sure beats trying to run a whole new wire the full length. Good job!