Can you just run a wire from point A to point B. In this case being that green wire you found with no continuity... I've heard someone had a similar issue in my quest to figure out my crank no start. It literally drove home, I drove around for a couple hours, turned it on and off several times during that period and then it just wouldn't start back up after the last time. I ran into the garage to drop off tools and got back in and it wouldn't fire. BTW where you getting all the diagrams from? This sounds like it's going to help me figure out my car even though it has the other engine in it. I've worked on my friends family car '06 1.8 silver coupe. I've done water pump, thermostat, belt, starter on it etc. His son just totaled it five feet from the house. So he replaced it with a grey 08 coupe. I actually stole the relays from it to test my car. I think I have the same issue because plugs were wet and when I sprayed in starting fluid it did nothing.

 

Basically, the relay is not properly receiving the signal from the PCM to activate the coils. I verified this by taking out the relay and jumping the 1 and 2 terminals with a paperclip - coils got voltage and car started up just fine (and yes I tested the relay too, it has not gone bad)

I tried starting fluid on my 2010 2.0l si and it didn't start. I want to go try the paper clip... Did you drive it like that? Power supply wire to ignition coils ('09 Si)

 

Anyone know which pin is 1 and which pin is 2? I'm trying to do this right now and see if it works. Thanks!

 

Does this look correct? Also, do I need to put the relay back in while jumping 1 & 2?

 

 

No that is not correct, not for my car anyways. I sent this to you directly, but here's what it looks like in mine

1 is "output", 2 is "battery +", 3 is "ground", and 4 is "signal wire". I believe both 2 and 4 would read battery voltage. As I said before, this what it looks like when standing on the driver's side looking down into the fusebox (with the relay removed).

And no, you can't put the relay back in, the paperclip is in the way haha.

 

I get my diagrams from lots of internet searches, as well as this online service manual (for 2006 Honda civics but they're pretty much the same as my 07)

http://civic.hondafitjazz.com/manual2.html

 

Thanks. It's supposed to be the same in my car too.

R11 is the ignition coil relay.
So it would look like this when standing in front of the car:

So....the ground off pin 3 is probably bad, causing it not to signal the relay to stay on. So after watching some youtube I figure it was pin 1 and 2, the copper contacts vs. the silver contacts. Then I came here and you responded yay! Usually on this forum there is no fix reported so I didn't think you'd respond lol

 

Thanks. It's supposed to be the same in my car too.
R11 is the ignition coil relay.
So it would look like this when standing in front of the car:

So....the ground off pin 3 is probably bad, causing it not to signal the relay to stay on. So after watching some youtube I figure it was pin 1 and 2, the copper contacts vs. the silver contacts. Then I came here and you responded yay! Usually on this forum there is no fix reported so I didn't think you'd respond lol

Yep, that's exactly right. Pins should all be the same in your car then.
There could be any number of problems with yours, really. Electrical repair is finicky stuff! Could be bad ground, could be a short on the signal wire, an open circuit somewhere, a short somewhere else, the list goes on haha. You have to do precise checks and tests with a multimeter to really narrow it down before attempting any repair

And yes I don't know what happened, I had set up email alerts but for some reason never got any about your replies to my post. But when you messaged me directly I got an email alert so I came and checked it out.

 

For anybody else who runs into this, I should give an update: I thankfully fixed my problem the very next day. For me, the short was inside the fusebox itself. Replaced it with a cheap scrapyard one and started up just fine, still running today

I realized I wasn't being very deliberate in my continuity checks. After finding a short from the relay pin to the PCM, but not finding any damage in the wire, I decided to isolate my checks. So, I unplugged that green wire from the fusebox, testing continuity from that plug to the PCM, and from that plug to ground. What do you know, perfect continuity, and no short-to-ground. Just to be sure, I then checked continuity from the relay pin to the pin on the bottom of the fusebox (aka, the pin the green wire was plugged into), and to ground. Sure enough, that's where the short was. You have to damage the fusebox to get inside and fix something like that so I just replaced it.

 

Thank you! I will run outside and shove a paper clip into pin location 1&2! Hope it works.

 

It didn't start. I think I had the paper clip in correctly. It felt tight. I can touch the multimeter lead to the paper clip with positive and put negative on the battery minus, and it should show voltage right? Either I did it wrong or that wasn't it. But last time I checked I had fuel and no spark because even starting fluid wouldn't kick. I have a fully charged battery and the starter sounds a little labored. Not sure if you know this but the starters on these, when they go out, they don't stop working just work slowly and that causes the issue?

 

yes the paperclip would show battery voltage if it's touching pin 2. Doesn't confirm that you have it seated in pin 1 correctly, but if it felt tight that should be good enough. Mine was even a little loose and still worked.

I'm not positive about the starter. But in general yeah I think a starter could be bad or going bad but still crank a little. I wouldn't jump to conclusions on that just yet though. If it were me, I'd confirm whether there is spark or not before trying to replace the starter, but it's up to you.

There's a lot of checks you could do. I'd probably start by making sure there's continuity from relay pin 1 to the ignition coils because that's the easiest. If you unplug the coils you'll see three wires in the harness. I believe the one you're looking for is black with a white stripe. Either the one on the right or the one on the left (pretty sure it's not the middle wire, but it's probably safe to check all three if you aren't sure which one it is). There should be continuity from that wire (on the female terminal of course) to pin 1. If not, you probably have an open circuit between the relay and the coils.

You checked your ignition coil 15A fuse, correct?

 

Yes, checked fuse, it's good. Okay, I'll try continuity test from pin 1 to coil plugs next. It's too cold and getting dark now so going to call it quits until next time. And in ten hours we are getting more snow. We already got 1 meter, 3 feet ..a couple of days ago. Thanks for all of your help, I'll report back.

 

Oh and I'd be surprised if stalling in gear at a dead stop caused it but I guess anything is possible haha
For me, the problem developed just overnight while the car was parked, had driven it just the day before with no issues. So could be coincidence

This page on this online FSM could be pretty useful to you if the continuity test passes.
Ignition Coil Relay Circuit Troubleshooting (R18A)

Hopefully you won't have to get to the point where you're dealing the PCM (can be a bit of a pain) but if you do, there's a trick you can do to get around the part where you have to use the Honda Diagnostics System, once again using paperclip lol
BUT before you do, assuming the continuity test checked out, it's probably easier to just literally check the plugs themselves for spark first. Just unplug and remove one of the coils and then take out the spark plug. Twist the ignition coil wire upside down and plug the coil back in (twisting the wire allows you to rest the coil on top of the spark plug hole, with the rubber boot part pointing up), and then pop the spark plug back into the coil, make sure it's in there good. Then you need to ground the spark plug, what I like to do is grab some jumper cables and attach one end to the spark plug (around the threads should be fine) and one end to battery negative (if you have those dual-type cables where it's basically one cable that splits into two leads at the ends, just make sure you're using the same color lead on each side, doesn't matter which color). Make sure you've got it hooked up right and that the cable leads aren't touching anything else. Have someone crank the car for a few seconds while you watch the spark plug tip. You should be able to see it sparking. If it does, then I'd start considering a starter issue. Be careful lol, we're talking very very high voltage here

Oof, good luck with the snow. Does not sound like fun doing all this diagnosis in that weather 😅

 

I've been nailing down a crank no start condition for the last week or so. I've now isolated the problem to the ignition coil relay circuit. It's a pretty specific problem so I feel I need to give some background info, it's a bit lengthy but bear with me.

Basically, the relay is not properly receiving the signal from the PCM to activate the coils. I verified this by taking out the relay and jumping the 1 and 2 terminals with a paperclip - coils got voltage and car started up just fine (and yes I tested the relay too, it has not gone bad)

On my car, the number 6 pin on the PCM connector A has a green wire that runs to the fusebox and eventually connects to Terminal 3 on the relay. This wire is how the PCM sends the signal for the relay to switch on. I tested for continuity along this wire - all good. Before suspecting a faulty PCM, I also checked for continuity from Terminal 3 on the relay to body ground...and sure enough there is, with about 400 ohms resistance (if that matters). According to the FSM, any continuity here means there is a short to ground somewhere on that green wire. However, after opening up the wire harness and examining the full length of the green wire, I could not find any signs of damage or shorts.

Am I just not looking closely enough? Am I wrong to assume the continuity test proves there is a short to ground? The only place left I can think of is inside the fusebox itself - somewhere between where the green wire comes in and the relay's Terminal 3. But of course that part of the fusebox is all sealed up so I can't check it out without damaging the box, and its specifically designed to prevent shorts etc., so is that even a reasonable assumption? I'd be happy to get a new fusebox instead of a new PCM, but I'd like to know for sure before I go replacing parts. Is it possible for a short-to-ground to develop inside the sealed portion of the fusebox, seemingly overnight?

Feel like I'm losing my mind after chasing down this electrical issue for so long, just need a steady head to tell me if I'm on the right track or not, and what other checks I can do to be sure of my short-to-ground theory. Or, to tell me I'm all wrong and it is indeed a PCM fault. Any help/tips/opinions is much appreciated

Hello I may have similar problem
Can you please help me out
My car was running fine but I took out the coil relay while the car was running at idle and the car died. It now cranks but won't start I have checked all relays fuses under the hood and inside the car they all check good
My questions is how do I check terminal 3 for continuity body to ground?

 

I'm having issue I parked car just fine ..next morning turns over I hear everything spinning but won't start .. getting gas and spark too.. I replaced the crankshaft position sensor and the camshaft position sensor and still nothing.. it's turning over but it's not giving the ignite sound as it would when you're normally cranking it over it's more quiet so to speak.. I took my valve cover off and the timing chain seems pretty darn tight so I don't know if I'm timing I don't see how it would if it's that tight.. help..

 

This is when I picked the car up, it had been sitting for a little bit. I drove it around for a couple hours fine.