Another Main Relay/Fuel pump issue post - Honda-Tech - Honda Forum Discussion


Another Main Relay/Fuel pump issue post

Reply
 
 
 
Thread Tools Search this Thread
Old 03-02-2017, 11:49 AM   #1
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Another Main Relay/Fuel pump issue post

Hello Honda-Tech, I just joined this forum today in search of answers after not being able to find anything through searching the forums on Google as well as the EF Facebook pages. I have a 91 civic si with a b18a1 running a pr4-a60 ecu. When I first got the car the cabin harness was hacked to s*** yet ran somehow. With a couple issues but it started and ran. Now that I have the harness replaced with an uncut one, the fuel pump does not want to kick on. The main relay clicks as it should, but the fuel pump does not prime afterwards. I tried jumping the fuel pump off the battery using a jumper wire and still nothing. So I assumed the fuel pump is faulty. But I wanted to make sure that power was being supplied after the main relay so I checked on a couple things. First off, ALL grounds including thermostat ground are good, showing very low resistance with readings of .1 or .2 if not all zeros on the multimeter. With the key at on (acc II) I checked the fuel pump connector with a test light and there is no light at the fp power wire. I also checked the main relay connector with the test light while the relay was plugged in (key also at on) and pins 4, 7, and 8 had no power. I had four extra relays laying around and went through all of them. ALL of them had three pins with no power. 7 and 8 always without power and between pins 4 and 5, depending on the relay. The one I have plugged in now is a brand new one with all the joints soldered but no power at 4. This was done earlier this week. But yesterday, come to find out the battery was dead along with the ignition switch acting up. I charged the battery and proceeded to test the car but the switch was still acting weird. With door open, the car does not beep when you put the key in but only after you turn it to the first position then still continuously beeps even at the on position (II). Then when I turn the key as if to start the car, it STILL continuously beeps 😑 The car also had an issue with stalling during idle when I first got it. So idk if this is an ignition switch issue, not distributing enough power to the entire system or what but I am lost at this point and no one seems to have any advice let alone the answer. Please help! Thanks in advance!
DrewED7pos is offline   Reply With Quote
Old 03-02-2017, 03:24 PM   #2
Honda-Tech Member
 
bbarbulo's Avatar
 
Join Date: Sep 2002
Location: CANADO
Posts: 2,267
Default Re: Another Main Relay/Fuel pump issue post

Don't get caught up in chasing too many issues at once. The beeping thing, I had an ignition switch that would do that, someone mashed it with a hammer, poured oil all inside the lock cyl, etc... in reality, the beeping is a little tiny switch mounted to the bottom of the lock cylinder. It is neither directly related to the lock itself nor the ignition switch. If it annoys you, pull the column cover off and take out one screw that holds it up. The beeping should stop. In my case the switch was fine, the actuator inside the lock cylinder was bad, so I ended up replacing the lock cylinder.

For the battery drain, remove the negative battery cable with the car off, and see what amperage is being drawn. Just hook up one DMM lead to the cable, the other to the negative battery post. Set the DMM to 10A draw, if it reads 0, then you can move to the mA readings (don't blow the fuse in your meter).

The main relay, I'm sure there are a million threads out there about troubleshooting power flow. Or just follow the wiring diagram in the service manual. Usually for every relay there is an input/output chart in there so you can verify that you are getting what you need with the key in whichever position you are testing for.
bbarbulo is offline   Reply With Quote
Old 03-02-2017, 06:34 PM   #3
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

Okay, well I guess I don't have to worry about the switch then. I was about to make a drastic purchase haha

As for the battery, I figured it would go out eventually since the car has been sitting for the past year...I actually did test it but I might've done it wrong, I'm still new at using a multimeter. I'll try testing it the way you had mentioned.

As for the main relay, I've seen the test procedure on this forum before and actually have tried jumping pin 1 to 7 and 5 to 7 on the relay connector. Should've mentioned that before, my bad. I also tried grounding (I forget which pin the test mentions) on the relay connector to find that doing these procedures does nothing. I also tried the ecu test where you leave the A connector out and do something with A16 and 17 I think (I was reading these tests on the forum off of my phone while I was doing these tests so I do not remember the exact procedures atm) all of these tests did nothing but I haven't done any tests involving the B or C connectors on the ecu. And as mentioned before, I jumped the fuel pump off the battery before it went dead and the pump did not kick on so maybe the pump is faulty? I'm sure I'd have to have a good working pump for these tests to work or show a problem within the circuit or relay. Also, I'm not sure I can believe all of these relays are bad...but then again they're all old except for the one I'm using. When you have the key turned to on(II), are all the pins on the relay suppose to have power? (Besides ground of course)
DrewED7pos is offline   Reply With Quote
Old 03-03-2017, 10:53 AM   #4
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

Bump! Need some suggestions honda-tech members!
DrewED7pos is offline   Reply With Quote
Old 03-03-2017, 03:31 PM   #5
Honda-Tech Member
 
bbarbulo's Avatar
 
Join Date: Sep 2002
Location: CANADO
Posts: 2,267
Default Re: Another Main Relay/Fuel pump issue post

lets start with the basics. did you check all your fuses? having had a cut up harness and having replaced all that, there is some chance you fried the PGMFI fuse; especially if you were in there jumpering stuff you have no idea what you're jumpering. Test all your fuses, one of them feeds power to your main relay and would explain why known good relays aren't doing what they're supposed to... they're not getting power. So start there before you get yourself into more exotic tests.

as for battery testing, there are three things. 1. does the battery have capacity to hold a charge, 2. is the alternator charging the battery (does not apply in your case since the car doesn't run) - use a battery charger and 3. is the car draining the battery when the car is turned off.

a multimeter can help you test 2 and 3. 1 is more difficult to do with a multimeter. I just use a load tester (cheap 100A one). The test I specified for you is for #3, see if the car is draining the battery when it shouldn't be. Unrelated to your relay issues (assuming there is enough juice in the battery to close the relay and turn the engine over).

I had a car so badly drained that I couldn't get the relays closed long enough to even push start the car.
bbarbulo is offline   Reply With Quote
Old 03-03-2017, 08:12 PM   #6
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

I haven't checked or tested all of the fuses... However, if by Pgmfi fuse you mean fuse #14 on the cabin fuse box, I know it's good. I remember when I first got the car, that fuse was blown and the main relay was bad. After I swapped in the good harnesses, I checked fuse 14 and it wasn't blown but I replaced it just to be sure. Even up to now, it hasn't blown yet. Are there any other fuses I should check?

As for the battery, thanks for suggesting different tests. I will have to wait till tomorrow evening to test my battery. I hope it's not completely drained but then again it would be nice if that was my issue lol
DrewED7pos is offline   Reply With Quote
Old 03-17-2017, 07:02 PM   #7
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

UPDATE: so good news, I finally got the fuel pump working! Last week I dropped the gas tank and tested the pump and turns out it was faulty after testing it. So I replaced it with a new one and now it is priming when I turn the key no problem. So whatever situation I was having before, it's been resolved.

Now, I have a new problem...the car will not crank at all when I start it. When I turn the key, there isn't even a click or anything from the starter. The car does absolutely nothing. The battery is fully charged, and I had the starter tested which checked out fine. Idk what to look for at this point. The car is a manual b18a1 and using an auto pr4 tho...so maybe that could have something to do with my situation? Need help asap!
DrewED7pos is offline   Reply With Quote
Old 03-17-2017, 07:52 PM   #8
Keyboard Humorist
 
4drEF's Avatar
 
Join Date: May 2002
Location: Granada Hills, Ca, USA
Posts: 9,554
Default Re: Another Main Relay/Fuel pump issue post

Start at the clutch pedal switch
4drEF is online now   Reply With Quote
Old 03-18-2017, 03:09 PM   #9
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

Hmm I was thinking that since yesterday but wasn't sure...would that keep the car from starting even tho it's running an auto ecu?

Nonetheless, I checked on the switch earlier and come to find out the small rod that contacts the top of the pedal wasn't even making any contact even with the clutch pedal to the floor and there also seems to be no rubber grommet or anything at the hole at the top of the pedal as well. If there is supposed to be a rubber piece there. So instead of pushing in the clutch pedal, I pushed on the little rod on the clutch safety switch (all the way in with my finger) while turning the key and still nothing.

So I assume a new clutch safety switch is in order? And if not, is there anything such as fuses, relays, etc relating to the switch I should check over?
DrewED7pos is offline   Reply With Quote
Old 03-20-2017, 01:24 PM   #10
Honda-Tech Member
Thread Starter
 
Join Date: Mar 2017
Posts: 7
Default Re: Another Main Relay/Fuel pump issue post

Bump! Just replaced the ignition switch, still nothing. No noise, no click, no nothing from the starter. Somebody please tell me why in the hell this damn car won't start!
DrewED7pos is offline   Reply With Quote
Old 03-20-2017, 02:57 PM   #11
Keyboard Humorist
 
4drEF's Avatar
 
Join Date: May 2002
Location: Granada Hills, Ca, USA
Posts: 9,554
Default Re: Another Main Relay/Fuel pump issue post

From what you described, the clutch switch is not working. Not sure if it will solve all of your problem, but it needs to be remedied.
It isn't ECU dependant at all.
The switch runs in line with the starter relay. If you don't push the clutch, then there isn't a ground feeding to the starter relay.

(If your car was originally an automatic, then it would have the neutral safety switch built into the gear selector that pretty much does the same thing.)


And then the starter relay...

4drEF is online now   Reply With Quote
Old 04-14-2017, 12:54 AM   #12
Trial User
 
Join Date: Apr 2017
Posts: 1
Default Re: Another Main Relay/Fuel pump issue post

Almost got the same problem 1990 4dr b18a1.... seems like a faulty fuel pump but works now and then......every time i turn the key to on...the wipers go on 1 to 3 times then try to start....most of the time can't hear the fuel pump working and when I do hear it it will start..not sure what to do I'm ready to drop the tank n change the fuel pump.....but could be a wiring problem somewhere in the car but i donnoo
Brad Gagne is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Checking Main Relay, with pics!!! Ahknodd Honda CRX / EF Civic (1988 - 1991) 34 03-01-2017 12:02 PM
*** Intermittent No Start Saga - 1996 Accord *** pullingin Honda Accord (1990 - 2002) 2 10-28-2016 02:56 AM
97 civic fuel pump/relay issue. No power Goobergobbler Honda Civic / Del Sol (1992 - 2000) 20 06-10-2016 01:05 PM
94 accord non vetech Waynecal19 All Motor / Naturally Aspirated 0 06-07-2016 01:07 PM
Car won' start, main relay OK, blown ECU? Nick7 Hybrid / Engine Swaps 1 05-14-2011 08:57 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -8. The time now is 08:57 AM.


 
  • Ask a Question
    Get answers from community experts
What's your question?
Send