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renda85
04-25-2009, 12:42 PM
I was wondering if someone can help me here, i was driving around all day yesterday with my laptop connected to my ECU (autronic plug n play) for logging.

i got home and turn off the car, then when i went to turn it back on car wont start. It cranks but won't start. So here is what ive troubleshooted so far.

-my walbro fuel pump doesn't prime (or make that wining noise) when i turn the key 2 clicks.

-I can connect to the ecu when i turn the key 2 clicks like i used to be able to do.

So im guessing shorted something while i was logging. Maybe the tip of the data cable touched the metal cover for the ecu.

if i cant connect to the ecu that means i have no power to the ecu. Plus no power to the pump.

i checked the Main fuse box, and took a look at the SBF's. I know how a regular fuse looks like when its blown, but what about the SBFs? how can you tell if those are blown?

any advice is greatly appreciated.

Mulder
04-25-2009, 12:49 PM
Check the "IGN" fuse in the under-dash fuse box.

renda85
04-25-2009, 01:00 PM
Check the "IGN" fuse in the under-dash fuse box.

check that right now, doesnt look blown, i changed it just in case, still a no go.

Cougar4
04-25-2009, 01:03 PM
When SBF fuses blow the link inside should looked seperated. The problem you are having may be due to a bad fuse in the dash fuse panel.

renda85
04-25-2009, 01:09 PM
When SBF fuses blow the link inside should looked separated. The problem you are having may be due to a bad fuse in the dash fuse panel.

i checked every fuse, they all look to be intact. What are all the fuses that control the fuel pump?

tekfoc
04-25-2009, 01:18 PM
bad fuelpump relay
also called fuelpump controller

The fuel pump controller is tucked away on the passenger side behind the rear strut tower. You'll have to pull all of the interior trim to get at it.

http://i431.photobucket.com/albums/qq33/tekfoc/fuelpumpcontroller.jpg

Cougar4
04-25-2009, 01:26 PM
i checked every fuse, they all look to be intact. What are all the fuses that control the fuel pump?

Check fuses 11 and 18 in the panel under the dash. Many folks have been fooled into saying the fuse is ok by just looking at them. A better investigation shows they are wrong. Verify that voltage is getting to both sides of the fuses using a test light probe.

renda85
04-25-2009, 01:52 PM
bad fuelpump relay
also called fuelpump controller

The fuel pump controller is tucked away on the passenger side behind the rear strut tower. You'll have to pull all of the interior trim to get at it.

http://i431.photobucket.com/albums/qq33/tekfoc/fuelpumpcontroller.jpg

thank you for the diagram, before i starting removing the trim i want to make sure its the relay.
My ecu still doesn't have power?

doesn't the ecu control the pump? so if the ecu doesn't have power then that means the pump wont turn on.

maybe the ecu is the culprit?

i have never changed a relay, can this be bought anywhere or only Subaru dealership?

Check fuses 11 and 18 in the panel under the dash. Many folks have been fooled into saying the fuse is ok by just looking at them. A better investigation shows they are wrong. Verify that voltage is getting to both sides of the fuses using a test light probe.

done, fuse's 11 and 18 have power and are working fine, i used a voltage tester.

tekfoc
04-25-2009, 01:55 PM
just take the old one out and bring it with you to the store.

I hope your wrong on the ecu $$$$

renda85
04-25-2009, 02:18 PM
just check all sbf fuses and they are fine.

im getting frustrated. how can i test the relay once i find it?

renda85
04-25-2009, 02:45 PM
just check the pump relay, when i turn the key the relay makes a click sound, im assuming this means the relay is in working order?

renda85
04-25-2009, 04:34 PM
bummmp

renda85
04-26-2009, 12:06 PM
anyone?

Cougar4
04-26-2009, 01:51 PM
just check the pump relay, when i turn the key the relay makes a click sound, im assuming this means the relay is in working order?

The clicking sound means the relay coil is working but that doesn't absolutely mean the switched contacts are making good connection. You have verify that with a voltage test and make sure the same voltage going to one side of the contacts is also going to the other side of the contacts while under load.

If the ECU isn't getting voltage then I would have to suspect a bad fuse as the cause though the Main Relay is in the circuit so that may be the trouble. When you checked the pump fuses, hopefully you checked both sides of the fuses to make sure they were ok. I suggest you also check the other fuses under the hood and make sure they are all ok with the ignition ON. Then check the fuses in the dash and verify they are good also. If the fuses are ok then it would be good to check the Main Relay.

renda85
04-26-2009, 07:46 PM
The clicking sound means the relay coil is working but that doesn't absolutely mean the switched contacts are making good connection. You have verify that with a voltage test and make sure the same voltage going to one side of the contacts is also going to the other side of the contacts while under load.

If the ECU isn't getting voltage then I would have to suspect a bad fuse as the cause though the Main Relay is in the circuit so that may be the trouble. When you checked the pump fuses, hopefully you checked both sides of the fuses to make sure they were ok. I suggest you also check the other fuses under the hood and make sure they are all ok with the ignition ON. Then check the fuses in the dash and verify they are good also. If the fuses are ok then it would be good to check the Main Relay.

thanks for the reply, i will check the pump with a voltage tester and check for continuity.

couple of questions on your reply. so your basically saying if my main relay did in fact go faulty, that would essentially be one cause to my ecu not receiving any power?

when you said "hopefully you checked both sides of the fuses?". what do you mean exactly? i checked the actual fuse with a volt tester and it was fine. do you mean to test the actual socket that the fuse goes in? with the ignition on?

EDIT: i just checked the 2 fuse sockets with the ign on, SBF#5 and SBF#6. SBF#6 doesnt work?

Cougar4
04-26-2009, 08:13 PM
The Main Relay supplies power to the ECU so if the relay is faulty the ECU will not have power, at least to some of it. There may be other power points to it also.

To check the condition of a fuse by looking at the voltage on the fuse you need to check both sides of the fuse if you use ground as a reference point for the meter. A bad fuse will show good voltage on one side but not on the other where as a good fuse will show the same voltage on both sides of it.

If you use a meter to measure the resistance of a fuse out of the circuit the a good fuse will show no resistance.

Akshunhiro
05-14-2009, 03:30 AM
Did you have any luck fixing this? I have a similar problem.

waveoff
06-20-2009, 08:16 PM
My car is exhibiting the same symptoms. My fuel pump won't prime and I can't connect to my ECU with my code scanner. It turns over just fine though. Usually, the CEL will illuminate briefly when you turn the key to ON but it's not doing that anymore. I don't think my ECU is getting power or got fried somehow. I had a UTEC hooked up and it has a red LED on it to show when there was power to the ECU/UTEC. The red light no longer comes on when the key is turned to ON to show that power is being supplied. What are some things I can check?

Cougar4
06-21-2009, 03:16 AM
You need to check the fuses under the hood and in the dash. Particularly make sure SBF-5 fuse under the hood is good.

jigga
06-21-2009, 09:02 AM
I hate to say it, but I think you guys may have fried your ECU's...

waveoff
06-21-2009, 07:53 PM
I don't know what it was but it's working fine now! No fried ECU here...whew! I checked all of the fuses and tested them all for continuity and they were all fine. I pulled the fuel pump controller and shook it a bit for the hell of it and put it back in since I couldn't find how to test the damn thing. Then I pulled the battery out and had it tested at vatozone and it tested fine. I put the battery back in and the car fired right up!

Cougar4
06-21-2009, 11:26 PM
The trouble may be due to a intermittent relay.

waveoff
06-21-2009, 11:45 PM
The trouble may be due to a intermittent relay.

Hmmm...maybe. Are you referring the the fuel pump relay specifically?

Cougar4
06-22-2009, 12:54 AM
No, the Main Relay for the ECU. I think the ECU controls the pump operation.

waveoff
06-22-2009, 01:35 PM
Ah, ok...gotcha.

waveoff
07-09-2009, 03:51 PM
Well, I found the source of my problem. I was having issues again with my fuel pump not running, no CEL displaying, not being able to connect to the ECU, etc. It turns out that it was a bad contact in my inside fuse box. I have my wideband o2 power wire tapped into the 15A IGN fuse via a tap-a-fuse connector. Yeah, I know, it's ghetto but I hate cutting into factory wiring. If I push on the connector, the main relay clicks and everything comes to life. I have since rewired my wideband power wire and everything works normally now. I was dreading having to troubleshoot this issue with my multimeter. Luckily it turned out to be something simple. :)

Cougar4
07-11-2009, 01:57 PM
Glad you found the source of the trouble and thanks for the feedback.