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47Woody
Learner
6 Posts
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 Posted - 03 Jan 2012 : 09:02:11 AM
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Hi Guys,
Got a VN V8 which just won't go. Purchased a manual for it but the instructions are a bit vague.
When I turn on the key only the oil light comes one. I earth out the check engine pin on the diagnostic connector and the check engine light comes on, but doesn't flash. If I earth out the diagnostic pin it does nothing. If I jump the diagnostic pin to the check engine pin it just continually flashes, no break to indicate any code.
I think that the computer is stuffed, should I just go to the wreckers and get another one, or buy an aftermarket chip to put in in. It hasn't been started for over a year with the battery out, so the chip may be dead.
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Edited by - 47Woody on 03 Jan 2012 09:22:54 AM |
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Mechknight73
National Driver
1001 Posts
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Posted - 03 Jan 2012 : 12:26:15 PM
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| The memcal chip on the ECM is supposed to be like a "hardwired" flash drive; it will remember the data on it regardless of whether it has power to it or not. For the process of elimination, you could get another engine computer. If it runs, all good. If it doesn't check through the harness. The lack of other warning lights is a clue you can't ignore |
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kingbucktoo
P Plater
54 Posts
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Posted - 04 Jan 2012 : 8:58:39 PM
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Could you explain your problem a little more. You turn the key and nothing happens except for an oil light??? Is the starter motor cranking the engine??
The ECM is not used to signal the Starter motor to turn, that is all to do with the ignition switch and maybe a relay in the engine bay.
If you are saying that the motor is cranking but its not firing that a whole new problem.
How fresh is the Battery, is it new / fully charged & have you seen it start a motor recently in the last week.
And yes it could be a ECM, You can get them from the wreckers ($45) V6 or V8 from VN or VP (if none ask for a JE Camria ECM make sure it has 1227808 written on the box some where), you just have to swap the MEMCAL (blue in colour) from yours to the new ECM. If the ECM is not the problem there is one more show stopper it's the EST (Electronic Spark/Timing module) mounted on LH guard just above the airbox. (If you have spark less likely the EST) but is sound more like the ECM as its not flashing correctly
Also have a look at the "How To Section" "Error Codes, how to get them and what they mean" sounds like your earthing the wrong pin, look at the first picture for the correct two pins to short out. Should be "Pin A to Pin B" (http://www.delcohacking.net/forums/viewtopic.php?f=10&t=219)
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47Woody
Learner
6 Posts
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Posted - 06 Jan 2012 : 11:53:50 AM
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Hi KingBucktoo,
thanks for replying, I will be a little more suscint with the problem.
Turning the key to ON, only the oil light illuminates, I expect the check engine light should come on and fuel pump go on for a couple of seconds. Are there any other lights that should come on?
Turning the key to start, engine cranks as expected.
Checks I have done:
EFI relay is sending power to injectors, power at injectors, but not clicking when cranking.
No spark when cranking.
Earthed out Diagnostic plug correctly - no CEL flashing on dash and I belive the engine fan should come one, it doesn't but confirmed OK)
Earthed out CEL on plug to confirm bulb OK, yes, illuminates OK
Battrey brand new with full charge.
Conected power to fuel pump connector on diagnostic connector and confirmed OK, nicely primed up with fresh fuel.
All other wiring functions (lights, horn etc) are working correctly
I have downloaded the diagnostic plug instructions from several sources and I am doing this correctly, except the damn thing won't flash anything.
I have had another suggestion that the Earths are not sufficient and thus the Computer is not working at all. Couple of main ones I can see, large cable -ve terminal to engine block, small cable -ve to body (suspect?), main wiring harness near relay box to body. Nothing else really jumps out at me.
I picked up from this forum about the VS O2 sensor earthing problems and I am going to try some extra earths near the ECU this weekend. Different problem but the strategy is similar.
Have tried to ignore the problem the last couple of days, but it hsn't gone away yet! Got another ECU from a VQ Statesman from wreckers yesterday ($150) complete, but am going to muck around with the earths before I plug the new one in so it doesn't get stuffed too. |
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47Woody
Learner
6 Posts
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Posted - 06 Jan 2012 : 3:59:24 PM
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Just another thought out of the blue, what about the anti theft module. I have never seen it in this executive Wagon, does it even have one?
Is it possble that the signal wire from the Anti-theft module to the computer is shutting down all functions. According to the wiring diags there is a direct wire to the ECU, should I try and give this pin a different value (gnd, 5v,12v?) |
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kingbucktoo
P Plater
54 Posts
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Posted - 07 Jan 2012 : 12:34:24 AM
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Anti-theft wasn't standard on a executive wagon. Unless you have an aftermarket anti-theft unit installed.
Ok My car with my anti-theft active I get no lights on the dash. when disabled the anti-theft I get engine check lamp, oil, handbrake lights on the dash, fuel pump runs for a few seconds stops, then it starts.
The only other suggestion is measure the voltage at the pins of the ECU for +ve battery voltage and then measure the resistance to the chasis for the earth of the ECU.
Also reading from my photocopied notes, Pin C16 ans B1 have +12V all the time supplied from the "engine fuse", the only other +ve battery voltage is a pink wire on pin A6 which should be +12v when the ignition is on.
The other thing is make sure the engine block has a good connection to the -ve of the battery. and if you can find the two earths from the ECU 1: earth terminal attaches to rear left cylinder head 2: earth terminal attaches to generator support
With no Check Engine Light illuminating the problem points more to the ECU.or earth |
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47Woody
Learner
6 Posts
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Posted - 09 Jan 2012 : 09:43:37 AM
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Problem solved thanks to KingBuckToo,
Decided to recheck all the earths and just scrape off a bit more paint to ensure a better connection and you wouldn't believe it, but at the earth connection at the back of the head, the battery terminal has attached, but the secondary earth connector (which probably goes to the computer) WAS HANGING IN THE BREEZE!!!
When I had the engine out to paint, I obviously missed putting the the 2nd ring connector back on, so it was a simple earth problem. A good point for all users of the forum, check earths first.
Now when you turn the key it fires up and runs, although fairly rough at the moment! Amazing! |
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HELP - diagnostic check won't work
