Engine doesnt stop when ignition ‘off’

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Might be worthwhile just doing the terminal 15 black wires in the ignition terminal block to earth, ignition off.

Do this both connected to and disconnected from the ignition switch. It should be 0V in both cases, but let's see.

When the ignition is off and the engine off, ignition switch block connected, is the generator warning lamp illuminated ?
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100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

itchyfeet wrote:
100leelee wrote:
itchyfeet wrote:Seen this before.
there are two circuits to the engine
one is ignition live the other is thermoswitched.
mix them up and you get this

Can you mix them up ignition switch end?
And how is it sorted..
Electrics not my strong suit..!!!

if its only been changed ignition switch end then you may have the ignition 12V permanently connected to permanent 12V
check the voltage on the coil black wire to body with ignition switch off.

Will do

Clearly somewhere along the line there is a rogue permanent 12v supply...
It’s just finding it....!!

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

if the coil circuit is 12V permanently it will drain your battery.
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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

rereading the first poat could be an ignition switch faulty previous owner bypased it?.
disconnecting batt earth won't help because alternatior is generating 12v.

need a kill switch on ignition 12v black wire
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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Coil shouldn't be live with the engine off if the battery earth is off, which I think it is, though it wouldn't do the coil much good either . It might be a permanent live to the coil, but the coil may have been live simply because it was picking up it's feed from the alternator.

For the benefit of Lee, itchy and I are I think both on pretty much the same page on diagnosis, just opting for different places to carry out similar tests.

The PO bodge of a starter button has already been removed......... Lee's just going through the process of eliminating the other PO bodges, this is another one of them :roll: let's get him back to standard
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:Coil shouldn't be live with the engine off if the battery earth is off, which I think it is, though it wouldn't do the coil much good either . It might be a permanent live to the coil, but the coil may have been live simply because it was picking up it's feed from the alternator.

For the benefit of Lee, itchy and I are I think both on pretty much the same page on diagnosis, just opting for different places to carry out similar tests.

The PO bodge of a starter button has already been removed......... Lee's just going through the process of eliminating the other PO bodges, this is another one of them :roll: let's get him back to standard

Thanks for all the info... really helps..
The switch operates ok, I mean you can start via turning the key.. really not sure why the po fitted a Frankenstein push button...
Who knows..!!

Will check all of the above and report back!!

Thanks again

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Re: Engine doesnt stop when ignition ‘off’

Post by bigbadbob76 »

100leelee wrote:It’s amazing how the po thought he was better than the engineers at Vw.

To be fair to the PO... Vw put in some very thin wires and very few relays, I imagine this was to save pennies.
I know my extra/upgraded wiring is better than what VW fitted, but then I'm an electrical engineer, maybe he had a little dangerous knowledge and bodged it. :roll:
Replacing wiring with thicker stuff reduces the chance of your van going on fire due to thin, old, and rotten wiring overheating.
It also improves the chance of your van starting and stopping. :D
The original VW wiring for the starter solenoid goes directly through the starter contacts of the ignition switch and after 30 years of this abuse the switch can fail.
Maybe that's why the PO fitted a push button starter switch. Fitting a starter relay would have been a better option though.
Hope you manage to make head and tail of his bodges anyway. :ok

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

bigbadbob76 wrote:
100leelee wrote:It’s amazing how the po thought he was better than the engineers at Vw.

To be fair to the PO... Vw put in some very thin wires and very few relays, I imagine this was to save pennies.
I know my extra/upgraded wiring is better than what VW fitted, but then I'm an electrical engineer, maybe he had a little dangerous knowledge and bodged it. :roll:
Replacing wiring with thicker stuff reduces the chance of your van going on fire due to thin, old, and rotten wiring overheating.
It also improves the chance of your van starting and stopping. :D
The original VW wiring for the starter solenoid goes directly through the starter contacts of the ignition switch and after 30 years of this abuse the switch can fail.
Maybe that's why the PO fitted a push button starter switch. Fitting a starter relay would have been a better option though.
Hope you manage to make head and tail of his bodges anyway. :ok


Yep, don’t fully know why it was done, but I know how badly it was done, so had to come out..!!

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

So before it started persisting it down...
Can confirm the only 12v feed to the ignition switch is the solid red cable.
No other wires have power.
Turn the key to other positions, power supplied to each wire..
The coil is not receiving 12v with the key in the off position.

There is one oddity.
There is a cable that is connected to the solid black wire, that seems to feed the oil pressure switch..
It is connected via a non std lamp on the side of the instrument binnacle..
Picture below..
That’s if the Haynes manual is correct...
This still appears to be live when the ignition switch is in the off position, but ONLY if the ignition switch has been turned on.. so if I reconnect the battery, no feed. Turn key on then off, feed still present.. so some kind of relay or latching action??

Looks like a replacement oil pressure lamp..?
But why it keeps its feed once it’s been live I don’t know.
Next step is to isolate this switch, then try to find this ‘latch’ that keeps the black ignition switch wires live.. think that is my problem...


The heater blower and wiper motor is live irrespective of what happens to the ignition switch...

Rain stopped play sadly

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

Image


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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

OK, so the red cable is from battery +ve terminal 30. That's a good start.

In the run position terminal X and terminal 15 should be live

if you had a green wire that should be live in the off position, and be 0V when the ignition is in run or start. You can read this from the diagram of the ignition switch.

The fact that the coil is 0v when in the off position confirms that the running on is caused by the coil being powered from the alternator in some way.

From an engine running perspective I think the front of the van is fine, though you should fix the green wire for the parking lights and follow through the wiring for the blower motor and wipers which need fixing. This may be another bodge or in some way related to this issue. Does the generator warning light illuminate with ignition on and engine off ?

Now you need to start looking at the back end of the engine and follow the physical cable connections against what the wiring diagram says.

I would start with disconnecting and isolating that non standard connection as you suggest and see if your test with ignition on / off gives the same result.

Then go to the connections to terminal 15 of the coil and see where they go to as a starting point.

I'll have another look at the wiring diagram and see if I can come up with something on the blower/wipers

Are there any "non standard" relays in the engine compartment
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Wipers and blower motor are all fed from "terminal x", and the x contact relay. This should only be live with the key in the run position.

Can you see if the heated rear window or rear fog lights (headlights on) are also working with ignition off
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:Wipers and blower motor are all fed from "terminal x", and the x contact relay. This should only be live with the key in the run position.

Can you see if the heated rear window or rear fog lights (headlights on) are also working with ignition off
No heated rear screen fitted..
Will check rear fogs

Thanks!!

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

100leelee wrote:Image


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clearly an add on disconnect it and see what happens.
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100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:OK, so the red cable is from battery +ve terminal 30. That's a good start.

In the run position terminal X and terminal 15 should be live

if you had a green wire that should be live in the off position, and be 0V when the ignition is in run or start. You can read this from the diagram of the ignition switch.

The fact that the coil is 0v when in the off position confirms that the running on is caused by the coil being powered from the alternator in some way.

From an engine running perspective I think the front of the van is fine, though you should fix the green wire for the parking lights and follow through the wiring for the blower motor and wipers which need fixing. This may be another bodge or in some way related to this issue. Does the generator warning light illuminate with ignition on and engine off ?

Now you need to start looking at the back end of the engine and follow the physical cable connections against what the wiring diagram says.

I would start with disconnecting and isolating that non standard connection as you suggest and see if your test with ignition on / off gives the same result.

Then go to the connections to terminal 15 of the coil and see where they go to as a starting point.

I'll have another look at the wiring diagram and see if I can come up with something on the blower/wipers

Are there any "non standard" relays in the engine compartment

The wiring to the coil looks standard to me, in so far that it’s tidy and logically cabled etc

There are a couple of non std relays, one looks like a fuel cut off, which would make sense as the van has an electric fuel pump, and one looks lpg system connected..
Yes, I have seen prettier wiring but nothing jumps out as odd..

As the van ran ok before the dash removal / wiring tidy up am still thinking that end. Haven’t touched anything in the engine bay apart from a replacement carb..

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