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AZmike
09-27-2002, 06:44 PM
My car has trouble 'catching' when trying to start sometimes, especially during the summer. A new main relay should solve this I've read here. The local parts places can't just get me one, they need to match it up. I'd like to leave mine in my car until I have a new one to replace it with since I need to be able to get to work, etc. Does anyone have an old one laying around that has any sort of part number on it. I tried Majestic Honda, but they only list 'reference numbers' not real Honda part numbers.

Has anyone used the Honda replacement? Does it actually work when it gets hot?

Thanks

anchovies
09-27-2002, 09:29 PM
yeah just replace it with an aftermarket one
pic taken from carotman's site
http://86-89accord.com/ezboard/EFI/mainrelay.jpg

DBMaster
09-28-2002, 08:15 AM
After I ordered the new one, I decided to play around with the old one. Removing the black plastic cover and cleaning the innards with tuner cleaner spray got it working again with no problems, but for $35 I was not going to risk getting stuck somewhere!

AZmike
09-28-2002, 08:32 PM
Thanks guys, I'll clean mine up for now. I know I've got some contact cleaner somewhere. I probably won't notice the difference until next summer--then it happens maybe 50% of the time. If it does, I'll be able to pickup the new one without puling out the old one now.

carotman
09-29-2002, 05:27 AM
you need toresolder the contacts, not just clean them

DBMaster
09-29-2002, 05:56 AM
I never noticed that the solder joints were bad, cracked, or otherwise damaged. It takes more than 130 degrees inside the car to melt solder.

Regardless, mine worked perfrectly for the week I waited to get the new one in the mail and it was causing starting problems about 75% of the time before that. We were lucky and didn;t have too many days 100 degrees or above last summer.

AZmike
09-29-2002, 09:17 AM
Ok, now it's sounding a lot more like a swap than a repair. Thanks again.

carotman
09-29-2002, 05:04 PM
The solder doesn't melt on the relay, it just breaks....

The main relay has the same problem as the light on the fan control buttons. (especially the fresh/rec)

smufguy
09-29-2002, 06:41 PM
yeah, constat usage wears those things off. damn, the internals look good, but yet they are bad. man.......

GreenMachine
09-30-2002, 02:05 PM
The part # is the same for every year, I have 3 layen around from differnt year 3rd gens and there all the same #, just to let ya know

buster133
10-03-2002, 07:20 PM
I replaced the main relay with an oem relay from Honda back in May when it started to get hot out. Since then, I have never ever had a problem. It looks exactly like the one pictured before and the part # was/is 39400-SE3-003.

carotman
10-04-2002, 03:13 AM
I still think that the repair method is more cost effective.... even if you need to buy some solder and an iron it costs less (plus you have a new tool to have fun with)

Low Tek
10-04-2002, 04:41 PM
Hey, I was just about to ask the same question - the relay deal.. my buddy is having the same problem, and then reading your question.. I now have the numbers needed.. this saves shop time..

Thanks guys

blh1983
08-28-2007, 04:32 PM
I have a Main Relay question. I know this thread is super old but... Here's my problem:
I thought I had an alternator problem because I went to start my car on the 23rd and it was dead. When I turned the key to the on position the first time the dash lights (PGMFI, Battery, etc.) were lit up bright as normal. Then I turned it to the start position and no power; the car was dead. So I jump started it and got it running but after I removed the cables the tach started bouncing around eratically and the battery light would get bright when I revved the engine. I took the car apart with the intent of replacing the alternator, but I wasn't able to break free the main bolt on the bottom; instead I just stripped the hell out of it. So I put the car back together with the intent of towing to a mechanic. I cleaned the battery terminals and just for the hell of it decide to see if my car will start up. And it does..

I thought problem solved so I get up the next morning try to start my car and it's dead.. Same exact issues. So I had a friend look at it. He tightened the terminals and it started right up. And it ran good for about 3 days. Then on day 4 I get up early start my car drive down the road and the tach starts bouncing around eratically and the battery light comes on. So I turn around drive it home, and turn it off and it starts up and runs just fine with out acting up at all. I drove it to work, then drove it home. And on day 5 it's acting up again not wanting to start acting like there's not enough power. Now mind you when I try to turn the car over all electical power to electronics is lost including lights; it's been this way the whole time that it's decided to act up. My car was running good for a day or two with no problems, and now this morning I went to start it and it won't start. The dash light indicators are half lit, and when I turn it to the start position all power to electical devices is cut completely off. So I kicked the car with my left foot by the fuse pane area and the lights on the dash returned to full power and the car started right up and is now running fine. Does this sound like an issue with my Main Relay??? Please help!

LX-incredible
08-28-2007, 09:11 PM
From what I gather, the main relay only has to do with ECU and fuel pump control. http://img527.imageshack.us/img527/6029/011988supplement62se321ve8.jpg (http://imageshack.us)
If you are loosing dash illumination, headlights, accessories, and the starter, your problem has to be with the battery cable connections or main fuses. If you are only talking of indicator lamps and not headlights, parking, or dash illumination, I would say look at the ignition switch. It appears to be a battery connection to me because you are saying that ALL power is lost when trying to start. The starter pulls a hell of a lot of current through those cables, any poor connections are going to reveal themselves then. Resistance = heat, feel around for it after trying to start. Check that the screws are tight on the main fuses, try removing the cables completely and sanding the connections clean, both on where they mount and the terminals themselves. Lastly, if you think that cutting the cable ends and putting those $2.99 lead terminals on will solve your problems, think again. You are usually starting with corroded copper to begin with, mating it with a different metal, and adding acid to the mix. What do you expect will happen? If you have to use the damn things, try to clean up the strands with some fine sandpaper and use dielectric grease.

blh1983
08-28-2007, 09:46 PM
Number 1, 2, 4 & 5 on the main relay are of high interest in the issue that I'm having. Do you agree? One thing that happens that I failed to describe is that sometimes I'll hear a clicking sound when I put the key in the on position. I have heard relays make this sound before but I have never dealt with a main relay; so I wasn't sure how they work. Again I kicked the lower dash area near the fuse box and the power that appeared to have been lost was restored to the lights on my dash and the car turned right over as if there were no issues. The cables are clean and tight in all locations that I have inspected.

LX-incredible
08-28-2007, 10:48 PM
Numbers 1, 2, 4, and 5 are all inputs to the main relay. It does not control the starter, nor the lights. The relay controls power to the ECU and fuel pump. I would say that your kicking moved the ignition switch, making contact, but you say that the dash illumination, dome light, and parking lights went out. Please correct me if I'm interpreting this wrong. The ignition switch does not control those lights. If you're sure that the problem is in the dash, check that the positive wire that supplies the interior fuse box is properly connected. The hazard, horn, door locks, interior light, and some others, do not even go through the interior fuse box. So, if you are indeed loosing all power, the battery, its cables (including fuse box and ground connections), and the battery (70A) fuse, are the only possible candidates. Feel for heat on the cables and connections, after starting or with all accessories on.