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 »

I know why you are saying what you are saying, but you are just going to have to go through a fairly logical process of diagnostic tests, if you start jumping around looking at random things it will take much longer to nail the problem I think.

I did wonder if you had an electric fuel pump, and maybe that in some way that was staying energised from the alternator and providing the current to the coil.

Go through the past few posts and do the suggested tests when you can keep dry, starting with the disconnecting / isolation of that red wire and if it's raining spend some of the time reading the wiring diagrams. The more you do the easier they become.
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:I know why you are saying what you are saying, but you are just going to have to go through a fairly logical process of diagnostic tests, if you start jumping around looking at random things it will take much longer to nail the problem I think.

I did wonder if you had an electric fuel pump, and maybe that in some way that was staying energised from the alternator and providing the current to the coil.

Go through the past few posts and do the suggested tests when you can keep dry, starting with the disconnecting / isolation of that red wire and if it's raining spend some of the time reading the wiring diagrams. The more you do the easier they become.

Will do
It’s annoying when things have been added / removed for no apparent reason.. guess that’s what happens over 30+ years..!!

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

Post by 937carrera »

I had a thought when I got up this morning.

Find and remove the terminal X relay (location shown on page 1 of the wiring diagram)

There seems to be a problem there, so remove the relay, you can redo the wiper / blower test AND you have eliminated that as being a potential part of the running on problem
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:I had a thought when I got up this morning.

Find and remove the terminal X relay (location shown on page 1 of the wiring diagram)

There seems to be a problem there, so remove the relay, you can redo the wiper / blower test AND you have eliminated that as being a potential part of the running on problem

Removed the X relay

Heater blower and wipers no longer work irrespective of the ignition switch.

Relay measures 68ohms across 85 and 86..??

The black wires from the switch are still live after turning the ignition off.
Double checked the switch just to make sure and it’s switching current as expected.

Disconnected the spurious wire into the engine bay, makes no difference.

So the constant live to the heater blower and wipers seems related to the Xrelay, or at least that live track.
The problem with the black wires continuing to be live even when the ignition is off remains..

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

Post by 937carrera »

I'm not sure what the spec for the coil resistance on the relay should be, but for the moment it isn't zero or infinity, so fine.

OK easy bit first.

X contact relay. I'm pleased the wipers etc are not working when the relay is removed. Can you do a continuity test across terminals 87 and 30. It should be open circuit, but I suspect the contacts are stuck together and so creating a permanent connection. You can leave it off until the rest of the wiring is sorted

Next thing is the operation of the ignition switch. Connector block removed.

Terminal 30 to terminal 15. should be infinity in the off position, no resistance in the run and start positions. I think that will be fine.

If that checks out then reconnect the connector (not pushed all the way home), switch to the run position and pull the connector off. Check for 12V between terminal 15 and earth. It should be 0V........ but let's see
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:I'm not sure what the spec for the coil resistance on the relay should be, but for the moment it isn't zero or infinity, so fine.

OK easy bit first.

X contact relay. I'm pleased the wipers etc are not working when the relay is removed. Can you do a continuity test across terminals 87 and 30. It should be open circuit, but I suspect the contacts are stuck together and so creating a permanent connection. You can leave it off until the rest of the wiring is sorted

Next thing is the operation of the ignition switch. Connector block removed.

Terminal 30 to terminal 15. should be infinity in the off position, no resistance in the run and start positions. I think that will be fine.

If that checks out then reconnect the connector (not pushed all the way home), switch to the run position and pull the connector off. Check for 12V between terminal 15 and earth. It should be 0V........ but let's see

Hi
Continuity between 87 and 30..
Will check the other tomorrow, but am pretty sure the first time the battery is connected, no 12v at terminal 15. If I operate the ignition switch to on, then turn back to off, I now have 12v at terminal 15.

Will double check in the morning, but am sure that’s how it is.

Will order up a relay from Brickwerks as don’t have a spare..

Cheers

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

Post by 937carrera »

Good, so the x relay is knackered, one more thing sorted.

I'm not quite sure how and where you did the tests for terminal 15. That's why I'm trying to be very specific about testing the switch in isolation first, and then the connector when it's been pulled off the ignition switch in the live position

When you pull the connector off, the 12v feed to terminal 15 should be disconnected because the ignition switch is no longer there, but as I said let's see
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:Good, so the x relay is knackered, one more thing sorted.

I'm not quite sure how and where you did the tests for terminal 15. That's why I'm trying to be very specific about testing the switch in isolation first, and then the connector when it's been pulled off the ignition switch in the live position

When you pull the connector off the 12v feed to terminal should be disconnected because the ignition switch is no longer there, but as I said let's see

Ok
Will do the full test.
Am sure though even with the switch connections disconnected there is 12v to the solid black wires. Pretty sure it’s not feeding through the switch when ‘off’..
But it seems to ‘latch’ as before the switch is energised there is def not 12v to the black wires.
Very strange!!

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

Post by 100leelee »

100leelee wrote:
937carrera wrote:Good, so the x relay is knackered, one more thing sorted.

I'm not quite sure how and where you did the tests for terminal 15. That's why I'm trying to be very specific about testing the switch in isolation first, and then the connector when it's been pulled off the ignition switch in the live position

When you pull the connector off the 12v feed to terminal should be disconnected because the ignition switch is no longer there, but as I said let's see

Ok
Will do the full test.
Am sure though even with the switch connections disconnected there is 12v to the solid black wires. Pretty sure it’s not feeding through the switch when ‘off’..
But it seems to ‘latch’ as before the switch is energised there is def not 12v to the black wires.
Very strange!!




So switch checks out OK

Did as you suggested, and after disconnecting the block terminal 15 does indeed still have 12v

I have a feeling this is somehow connected to the lpg install.. but still, terminal 15 shouldn’t be live if not fed through the ignition switch from terminal 30..? I think

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

Post by 100leelee »

100leelee wrote:
100leelee wrote:
937carrera wrote:Good, so the x relay is knackered, one more thing sorted.

I'm not quite sure how and where you did the tests for terminal 15. That's why I'm trying to be very specific about testing the switch in isolation first, and then the connector when it's been pulled off the ignition switch in the live position

When you pull the connector off the 12v feed to terminal should be disconnected because the ignition switch is no longer there, but as I said let's see

Ok
Will do the full test.
Am sure though even with the switch connections disconnected there is 12v to the solid black wires. Pretty sure it’s not feeding through the switch when ‘off’..
But it seems to ‘latch’ as before the switch is energised there is def not 12v to the black wires.
Very strange!!




So switch checks out OK

Did as you suggested, and after disconnecting the block terminal 15 does indeed still have 12v

I have a feeling this is somehow connected to the lpg install.. but still, terminal 15 shouldn’t be live if not fed through the ignition switch from terminal 30..? I think


As terminal 15 is not live upon initial connection of the battery, somehow this is happening only after switching power to that circuit..., then stays live... very strange

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

Post by 100leelee »

Plus maybe the van has always had this problem but was masked by the engine being stopped by lack of fuel via the lpg cut off, rather than the lack of ignition..

Just a thought

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

Post by 937carrera »

100leelee wrote:Plus maybe the van has always had this problem but was masked by the engine being stopped by lack of fuel via the lpg cut off, rather than the lack of ignition..

Just a thought

Possibly.

So you have confirmed that the ignition switch is working properly, and that terminal 15 at the connector remains live when disconnected from the ignition switch. That is what I thought would happen.

This means the problem is not at the front but at the back.

There are three forks in the road at this point

1. Pull the fuel pump relay and repeat the previous test (it's a hunch, but easy to do)
2. Attack the problem from the coil wiring
3. Attack the problem from the thermoswitch wiring (remember, itchy said he had seen something like this problem before)

|suggest you do 1, just because it is easy, and then decide whether to do 2 or 3. Whichever you choose, you need to check and tace all the relevant wires, and compare them to the wiring diagram.
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:
100leelee wrote:Plus maybe the van has always had this problem but was masked by the engine being stopped by lack of fuel via the lpg cut off, rather than the lack of ignition..

Just a thought

Possibly.

So you have confirmed that the ignition switch is working properly, and that terminal 15 at the connector remains live when disconnected from the ignition switch. That is what I thought would happen.

This means the problem is not at the front but at the back.

There are three forks in the road at this point

1. Pull the fuel pump relay and repeat the previous test (it's a hunch, but easy to do)
2. Attack the problem from the coil wiring
3. Attack the problem from the thermoswitch wiring (remember, itchy said he had seen something like this problem before)

|suggest you do 1, just because it is easy, and then decide whether to do 2 or 3. Whichever you choose, you need to check and tace all the relevant wires, and compare them to the wiring diagram.

Ok

1. Pretty sure there is no relay for the fuel pump. It’s an aftermarket fitment,.
2. And 3. Will see what’s what

Still unsure as to why on the initial hook up to the battery, no feed to terminal 15, but after cycling the ignition switch there is a permanent 12v supply to terminal 15.

?

Oh and many thanks btw for your help so far!!!

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

Post by 937carrera »

100leelee wrote:[
Still unsure as to why on the initial hook up to the battery, no feed to terminal 15, but after cycling the ignition switch there is a permanent 12v supply to terminal 15.

If I knew I would tell you, I can't figure it out remotely, but do remember itchys earlier comment.

Tackle it from the coil end. Try this

Ignition switch still connected, terminal 15 pulled off the coil. Do the off/ on / off test with the meter at the coil. I think it will still show 12v when returned to off. Leave the coil connection off.

Take a look inside the black junction box (left front of the engine bay) Is there anything in there that looks aftermarket, extra wires, especially on the two white 7 pin plugs
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:
100leelee wrote:[
Still unsure as to why on the initial hook up to the battery, no feed to terminal 15, but after cycling the ignition switch there is a permanent 12v supply to terminal 15.

If I knew I would tell you, I can't figure it out remotely, but do remember itchys earlier comment.

Tackle it from the coil end. Try this

Ignition switch still connected, terminal 15 pulled off the coil. Do the off/ on / off test with the meter at the coil. I think it will still show 12v when returned to off. Leave the coil connection off.

Take a look inside the black junction box (left front of the engine bay) Is there anything in there that looks aftermarket, extra wires, especially on the two white 7 pin plugs

So....

No dodgy wires inside the junction box at all.
Still have 12v at terminal 15.

So looked around to see what else is live in the engine bay when the ignition is off.
The wiring to the carb is live in this state.
The feed wire from the relay is live, thick red wire inside a tube with a smaller black wire.
The wiring here could be the problem as the black and red wire are essentially connected, which seems odd.
The relay checks out ok, in so much that it’s open when supposed to be.

If I remove the relay, get no 12v to the coil, when it’s supposed to be off, but do get 12v to the coil when the ignition switch is on..

What does this relay do?

To check the wiring to the carb:
Took a photo

Essentially the thicker red wire from terminal 30 on the relay goes to choke and part load duct heater.
Due to a dodgy join it also feeds the thinner black cable that goes back to the junction box I believe.
It’s messy, which looks suspect

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