Rebuilt ka killed my ecu? Help

Post by **komete** » Sun May 25, 2008 1:58 pm

I just finished rebuilding my KA a few weeks ago and got it running good. I think my alternator is going bad but I'm not sure. Yesterday I flashed my hi beams and my car died but came right back on when I released the hi beam. SO I was going to go take it to autozone to have my alternator tested.

Well today when I went to crank it nothing happen. NO engine lights came on or anything. I took a look at the ecu and the red light on it won't come on either.

I've pulled most of the fuses and none were blown. It's like the ignition, ecu, and dash lights are not getting any power. I have a volt meter but don't know where to start to diagnose. Can anyone advise?

Post by **slo_coupe** » Sun May 25, 2008 2:01 pm

put a new alternator and charge your batt

Post by **komete** » Sun May 25, 2008 2:28 pm

slo_coupe wrote:put a new alternator and charge your batt

The battery does have power. I checked it with a volt meter and it was 12.45. The battery was just bought a week ago. The dome lights, emergency lights, etc do come on. Just the ECU and dash lights seem to be dead.

Post by **EstoMax** » Sun May 25, 2008 3:44 pm

you killed a fuse or relay.. check them. i bet theres some kind of a short with your high beams that caused them to blow something. my bet is on the EGI relay

Marko

Post by **komete** » Sun May 25, 2008 4:20 pm

EstoMax wrote:you killed a fuse or relay.. check them. i bet theres some kind of a short with your high beams that caused them to blow something. my bet is on the EGI relay

Marko

If the EGI rely is blown would there be no power going to the ECU and dash lights? LIke check engine lights, break lights etc? Also I'm a noob with a volt meter, can you give me a little direction on how to check for shorts etc with one?

BTW I just checked and my headlights will not come on. Something's blown. THink I need to change my name to Blown 240.

All I want to do is just drive the damn thing to work... arghhhh
Modified by komete at 7:38 PM 5/25/2008

Post by **komete** » Mon May 26, 2008 6:43 am

bumb for help

Post by **assassin7420** » Mon May 26, 2008 7:13 am

check everything in the fuse box under the hood.

Post by **HurryupandrunS13** » Mon May 26, 2008 7:51 am

Load test the battery. It may sit 12.4, but under load it may drop drastically. Even if it's new, a bad alternator will kill a brand new battery. Check your charging voltage while it runs, 13ish volts should be the least.

Post by **komete** » Mon May 26, 2008 7:58 am

You don't understand I can't crank it, It won't crank. when I turn the key to the on position there is nothing. No engine lights, no power to the ecu, it's almost like the battery is unplugged. I've looked at every fuse and they all look good. The only electronics that work from what I can tell is the dome light and emergency lights and the dash dinger that makes a noise if you leave your key in the ignition. Everything else is dead.

Post by **ca18detgabby** » Mon May 26, 2008 8:09 am

you have a bad ground or cut in one of your lines and it is drainning the system.

an alternator has nothing to do with starting a car....

I would guess you have a bad connection somewhere and it is grounding out, and was cut or atleast stripped when you plugged it back in.

if you have no power when you openned the door you have either a drained battery or a **** load of blown fuses.

since your dome turning on I would expect you battery to be low voltage, if there is an issue with your charging system then taking it out and rebuilding it is pretty cheap. I would check my connections before I did anything else. might also check your fuseable link before you blame the alternator.

PS a dome light takes little or no power to light. it takes far more power for the enine to crank.

Post by **komete** » Mon May 26, 2008 8:16 am

I do believe there is a short or maybe a relay is blown. I know it's not the battery. When there is a drainage problems and you turn the ignition to on the dash clock will go out but it stays on. Also the emergency lights and dome light stay on. There is no drop in voltage. Something between the Headlights, ecu, and ignition is toast. I've checked every fuse and visually every one looks good.

Sumation:no power to Headlights no power to ECUno power to ignition

Post by **ca18detgabby** » Mon May 26, 2008 8:55 am

komete wrote:I do believe there is a short or maybe a relay is blown. I know it's not the battery. When there is a drainage problems and you turn the ignition to on the dash clock will go out but it stays on. Also the emergency lights and dome light stay on. There is no drop in voltage. Something between the Headlights, ecu, and ignition is toast. I've checked every fuse and visually every one looks good.

Sumation:no power to Headlights no power to ECUno power to ignition

time to go buy a bunch of fuses.......they are mad cheap anyway and always good to have a back up. replacing all of them and you remove that from the equation. just because visually it looks good.... doesnt mean it isnt the issue.

also a blown fuse for your turning HLs will not stop the car from starting.

time to check your relays.........

I still feel that there is an issue with something grounding out.

just for sake of taking the battery out of the equation, barrow someone with a good battery and test it.

it isnt a problem with your ignition switch as the HLs will work w/ or w/o the car on.

Post by **komete** » Mon May 26, 2008 9:18 am

ca18detgabby wrote:
time to check your relays.........

I guess I'll stop by auto zone and pick up some fuses. Do you know how to check a relay? I still haven't figured that one out.

Post by **komete** » Mon May 26, 2008 10:51 am

I just checked every fuse with a fuse tester and they are all good. Now I need to test relay's. Can anyone tell me how I can test a relay?

Post by **komete** » Mon May 26, 2008 12:44 pm

OHM testing on all the relays was good. I then used a volt meter and put the key on and only a few of the relays were getting power to there connectors(the female part you plug the relays into). I'm thinking whatever is blown is before either fuse box. Any ideas?

Post by **LayNLow240** » Mon May 26, 2008 1:12 pm

Start tracing the wires back to see if there are any cut/exposed/melted wires. Good luck with that.

Post by **komete** » Mon May 26, 2008 2:33 pm

I've pulled all the relays I could find and only one is suspicious. It has a black top and I think it is the Recirc relay. It is located by the fuse box on the the drivers side. One of the prongs, this one has 5, is darker than the rest like it has seen higher voltage than it is supposed to. It's not black but it does look more corroded.

Anyone knows what a recirc relay does?

Post by **komete** » Mon May 26, 2008 2:48 pm

This is a link to the relay in question. No idea what it does yet.http://www.courtesyparts.com/M..._Code=

Post by **komete** » Tue May 27, 2008 4:23 am

komete wrote:This is a link to the relay in question. No idea what it does yet.http://www.courtesyparts.com/M..._Code=

Bump to see if anyone knows what this part does

Rebuilt ka killed my ecu? Help

Rebuilt ka killed my ecu? Help

Re: Rebuilt ka killed my ecu? Help (komete)

Re: Rebuilt ka killed my ecu? Help (slo_coupe)

Re: Rebuilt ka killed my ecu? Help (komete)

Re: Rebuilt ka killed my ecu? Help (EstoMax)

Re: Rebuilt ka killed my ecu? Help (komete)

Re: (assassin7420)

Re: (HurryupandrunS13)

Re: (komete)

Re: (ca18detgabby)

Re: (komete)

Re: (ca18detgabby)

Re: (komete)

Re: (komete)

Re: (LayNLow240)

Re: (komete)

Re: (komete)

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