Howdy folks, i have had this happen in the past with these freaky little trucks and it's typically resolved with a new scv or a connector repair but this time not so lucky. It's a jo5 motor and i'm using hino dx. Iv'e got continuity to and from the connector but i'm not getting any voltage to the specified pins on my check harness. dx is telling me the standard is 12-0 volts, my question is if i have a 12v battery how can i ever have anything other than 12-0 volts? I currently have 0 volts so that means it's ok? i know someone on here can set me straight. OH and i replaced the valve too since i had one on hand. Thanks.
2006 hino 185 with p0268 scv malfunction
- Thread starter Lt1struck
- Start date
danthewolf00
Veteran Expediter
No 0 volt means 0 nothing.
I wouldn't trust the troubleshooting 100%. Verify that you're on the right pins.
I would load test the wiring vs. a continuity check. Multimeters lie.
It's saying you're looking for a pulse wave of 0-12v. The SCV is pulse width modulated. Ideally you'd use an oscilloscope.
I would load test the wiring vs. a continuity check. Multimeters lie.
It's saying you're looking for a pulse wave of 0-12v. The SCV is pulse width modulated. Ideally you'd use an oscilloscope.
The firewall junction box is a water magnet, might want to check inside.
The troubleshooting is quick to blame the ECU, but I've never had to replace one. In my experience it's always something else.
Just an idea, you could run an overlay to the scv and see if that fixes it.
The troubleshooting is quick to blame the ECU, but I've never had to replace one. In my experience it's always something else.
Just an idea, you could run an overlay to the scv and see if that fixes it.
I have dealt with water in the box before and now its the first place I look. I did run an overlay finally and no dice. I couldn't find anything else so we took the pump off and low and behold the shaft spins freely, no resistance at all. The odd thing to me is that the 268 has a very similar pump with the same scv and they never give me cel when they go bad, and we've changed several of them.Thanks again Greasy
Glad you sorted it out. The troubleshooting suggests it's a circuit code, but it seems to be a performance code instead.
I just had a thought. Even if the scv was totally dead, it should still make fuel pressure. The scv is wide open with no power to it.
If there was no fuel flow/pressure and the pump has an uninterrupted fuel supply, then it has to be a faulty pump vs an scv.
If there was no fuel flow/pressure and the pump has an uninterrupted fuel supply, then it has to be a faulty pump vs an scv.