Crx Ecu???!!!!

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rawerz

New Member
I have a 1990 Honda CRX that I just bought in a non running condition. The first thing I check, seeing as to how it doesnt run, the ECU for any codes. I get NOTHING, not even one blink. I checked my battery, terminals, and reconnected the ecu cables. I turn over the car 2 clicks and still no blinks?

Does this mean i need a new ECU? or whats happening?
 
well it could be that its an electrical problem that wont be recorded in the ECU. Does it crank but not start?

Where in texas do you live again. I might be able to look at it if you are in the dfw area.
 
Checked my fuses and they are good. Tried a difefrent battery and still no blinks. I checked for fuel and I get no fuel at all but I still have a spark. It turns over fine just will not start, of course due to no fuel.
 
main relay ftw.

time to drop the tank and see if you have power at the fuel pump.

if yes, replace fuel pump.

if no, replace main relay.

if yes and fuel pump kicks on (loud buzzing sound when you turn the key to 2) time to really check over the fuel system.

If it is either of those things, the ecu wouldnt know it.
 
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I guess im going to go threw the fuel system then...

Another question.

I thought the ECU was suppose to blink at least once , like a "hello im alive" blink?
Is that true?
 
on obd1 cars itll stay solid then turn off i think. doesnt blink again after that.
 
Well I get no light at all! Not even an intial blink.
 
Ok now. I was checking and I have no fuel coming threw the lines and now my motor wont even turn over just the starter will click.

But I crawled back under the dash checking the fuses and the "starter solenoid valve" 10 amp fuse pops everytime I turn the key over. And the fuel pump only clicks one time very swiftly.
 
Sounds like the starter solenoid is short circuiting. Replace that and charge your battery, cuz it might be dead from all the cranking.

As far as your fuel, could be the fuel pump relay, or the fuel pump itself. The lines should pressurize when the key is on, so if this doesn't happen (assuming the battery has a charge). Then you need either a pump or a relay. Test the relay before you go and drop the fuel tank.
 
Is the fuel pump relay and the main relay 2 different things? If so where is the fuel pump relay located?
 
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It's on the left, left of the coin box. Pretty difficult to get to if you're big(hell, I had a hard time and im 5'6).

Yes, theyre the same thing. The main relay is two relays in one box.
 
Alright, here's my thoughts about what's goin on here.
1. Stop obsessing over your ECU light
2. reikoshea has told you what could be causing that 3 times and you fail to understand what he's talkin about.
3. This is an electrical problem.
4. That means you need to use a volt meter and check circuits.
5. The main relay is under the dash by your left knee and is responsible for turning on your ECU and Fuel pump when you turn the Key to the ON position.
6. That COULD be why your ECU light isn't blinking once.
6a. Or your ecu could be shot
6b. Or the LED on the board simply doesn't work, rare but happens.
7. The causes listed in #6 is what we're trying to nail down.
8. If you have another ECU handy, throw it in and let us know if the light blinks.
9. If you don't have another, then do what we're sayin to do to find out if the main relay simply isn't coming on.
10. If your starter clicks but can't turn the car over, your battery is dead. Charge it. If it doesn't hold a charge, replace it.

Now read #5 again.
Then #4.
Now use the volt meter and check for 12v+ at one of the 2 or 3 wires at the Fuel Pump when you immediately turn the key to the ON position.
 
The main relay was bad. I ordered a new one from parts train today. Ill update after I get it. Thanks guys. Sorry about the hard head.
 
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