jamesinc
You can test some voltages using this guide:
Slowbrick
Pink label ECUs fail in some very strange ways and are by far the most notorious of the bunch. 9xx series ones are the pick of the bunch and I've never heard of one failing. White label ones are better than the pinks but not hugely. If you replace it then get a 9xx if you can and if not then get a white. Don't get another pink one. They are too unpredictable.
lasercowboy
Do check for the pre-fuel pump fuse/wiring. I had a similar set of symptoms with my 240 recently, and tried a different ECU, EZK, pump relay, etc.
It turned out that the wiring for the pre-fuel fuse had too high resistance, so even though it showed continuity (and generally correct voltages in the right places) it wasn't letting enough current through.
EDIT: here's the thread:
https://ozvolvo.org/discussion/5873/240-electrics-no-juice-getting-to-fuel-pumps#latest
lasercowboy
Actually, reading the first few posts of that thread back (reminding myself of the symptoms) it sounds very similar to what you're experiencing.
familyman
@lasercowboy - I'm reading through it now. You mean the 25A spade fuse? It seems my year model doesn't have it.
Note 1: My diagnostic position 2 LED is already on bright before I press the button. Then press the button and the LED stays on (it never changes even for that split second as you press the button) - and of course, displays no codes. Whereas the position 6 LED glows very dimly with probe in, and displays codes as it should.
The #2 LED being either always on - or dead - is what I'd expect to see from a device with fried integrated circuits.
Note 2: You had no spark, whereas mine does.
Note 3: Noting this comment from @tbro :
"I know with K-jet there can be no spark if the fuel relay fails , its cuts power to the ign module, maybe same??"
... Now when I was reading about faulty ECUs, I found an old comment that said that same thing... That green fuel pump relays used to control/kill spark, but white relay cars move that function into the ECU! That other guy then quoted someone else HE read somewhere, who claimed a possible fix was to use a green relay, but only after swapping the pins in the relay socket around to suit - thus the green relay has the required circuitry that dies in the white relay car's ECU...
... And in another thread I saw, an electronic technician built his own circuit based on a 555 timer to replace a pulse that dies in the ECUs - which feeds the EZK I guess(!?) - I forget the details now - but that page turns up constantly during searches.
So these again point to the ECU.
I'm just waiting for some email replies now, about different numbered ECUs - to decide which one to use.
familyman
LOL. I was just looking at the circuit diagram... Take note of fuse 6! Anyone have any idea what they're on about there? 2x circuit lines, 2x fuses, both connected to the same point at the dot. (Why not just one line, one fuse - like fuse 4 just above it!?)
jamesinc
I would assume you satisfy the current requirements of that circuit, rather than using one thicker wire.
familyman
What's going on with terminal 22 on that pic on the previous page? (It has 2x terminal 22s on the list.)
lasercowboy
Humour me. Run an independent wire directly from the positive battery post to where it splices in for the relay, ecu and ezk.
carnut222
Every time I see an email about a new post to this thread I hope the answer has been found. Alas, still working! May be time to call somebody to cast the demons out LOL!
familyman
I Just showered, so shall do tomorrow. But where exactly do you mean?
a) Terminal 1 & 6 of the fuel relay (orange wires) both connect together, then go off to the injectors.
b) Terminal 3 of the fuel relay (which is connected to fuse 6 which I've been applying power to both sides of at different times throughout this) goes to terminal 5 of the EZK, and 4 on the ECU (red wires).
Slowbrick
I might have a spare pink ecu here for you to try. Ill have a look tomorrow.
familyman
You... actually KEPT - a pink one!? LOL.
lasercowboy
familyman;117634 wroteI Just showered, so shall do tomorrow. But where exactly do you mean?
a) Terminal 1 & 6 of the fuel relay (orange wires) both connect together, then go off to the injectors.
b) Terminal 3 of the fuel relay (which is connected to fuse 6 which I've been applying power to both sides of at different times throughout this) goes to terminal 5 of the EZK, and 4 on the ECU (red wires).
Terminal 3 of the relay. It at least eliminates a high resistance connection to that pin as the cause. The reason I think it might be that is it would potentially produce the unique set of symptoms that you have by causing apparent faults in all devices (which otherwise appear to work independently ok).
familyman
lasercowboy;117678 wroteTerminal 3 of the relay.
* Connect terminal 3 to battery +ve
* Crank, no pumps, no start.
* Jumper 4 & 6 to run pumps, crank, no start.
lasercowboy
You left the existing connection to terminal 3 in place, right? (cos my theory requires that the other things spliced onto that connection would also be getting under-supplied, not just the relay).
If so, I'm stumped, sorry!
familyman
Yep, was still all connected.
Since I have spark and can force the fuel pumps to work, I was thinking could I start the car if I grounded the injectors manually with a switch, LOL. But I don't know enough about what goes on inside the ECU - I might short out something else.
familyman
Anyone know if the EZKs are prone to failure too? (I'm planning to buy a stock of common-failure parts.)
familyman
951 ECU ordered. ~10 day wait.
Major Ledfoot
familyman;117607 wroteWhat's going on with terminal 22 on that pic on the previous page? (It has 2x terminal 22s on the list.)
How pin 22 works depends if the car is question has a PTC or NTC thermistor for the EGR sensor. So it's listed twice since different ECUs will look for different conditions.
PTC thermistors are on pre-92 cars, and NTC thermistors are fitted to post 92 cars, according to TP 32043/1, p25.
