Immobiliser with keypad on XUD

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wennbom
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Immobiliser with keypad on XUD

Post by wennbom »

I'm desperate!!

I have a 2001 Suzuki Samurai SJ419TD with:
- 1.9 TD XUD engine
- Lucas fuel pump
- Immobiliser with keypad

This car is to be converted to something called an A-tractor in Sweden. Basically you limit top speed to 30km/h and the kids from 15y can drive it.
Speed is limited by means of operating the fuel solenoid with a controller and a solid state relay which is fairly straightforward were it not for the bloody immobiliser.

The immobiliser has to go. I have started but clearly I'm lacking in understanding how it works and what I need to do to disconnect it completely.
Step 1 before installing the speed controller is to get the engine to start (and stop) without immobiliser.
I have identified 3 main components
a. immobiliser keypad
b. start/stop solenoid
c. Bitron double relay

Removed the fuel pump armour and have replaced the "smart" 3-wire solenoid with a 1-wire one.
Feeding the Bitron relay input pin that normally comes from the keypad with 12v coming from the ignition barrel.
I can hear 1 of the relays in the Bitron pull ok but I only get 1.5V on the solenoid output instead of 12V so the plunger does not lift.
Tried feeding the solenoid directly from the battery - plunger lift and there is fuel - but it won't start.

I need HELP:)
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

I've understood that the Bitron maybe is connected like this:
Just 5 wires in it.

1 - fuel pump supply (this is connected to the start/stop solenoid)
2 - relay coil supply (+12 after the ignition switch)
3 - ??? Purple wire from Keypad

10 - ground control from the ECU (fuel pump, lambda probe coil and heater control)
11 - direct +12 from the battery
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wheeler
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Re: Immobiliser with keypad on XUD

Post by wheeler »

First off have you actually seen this engine run before you done any modifications to it? If so when was the last time the engine ran? does it have an underlying issue you may not be aware of?
If you put 12v to the stop solenoid this should be enough for it to start & run.
have you loosened the fuel pipes at the injectors to bleed & see if fuel is getting there?
Have you tried giving it a sniff of easy start?
oscar
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Re: Immobiliser with keypad on XUD

Post by oscar »

Once dearmoured and connections bridged the Keypad is surplus as you just need an ignition fed live

Hardest part was drilling fixings out to remove plate
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

Thanks,
Yes, the car ran good 1h before I started modifying it and it started very easily.
I also had the engine running after removing the armour while trying to figure out the immobiliser.

No, I have not checked at the fuel injectors but I can hear the solenoid pull and there is fuel in the plunger seat.
Is it as simple as disconnecting one of the injectors and crank the engine?

Possible causes
1. New solenoid isn't working as it should since the engine is not starting even with 12v direct feed to it. This is the one I got https://www.autodoc.co.uk/fae/2496521
2. Bitron relay and /or immobiliser is controlling something else. On the Bitron relay I (now after removing the original 3-wire solenoid) only have 1.5v on the grey fuel pump supply wire.
What does pin 10 do? (10 - ground control from the ECU (fuel pump, lambda probe coil and heater control) )
wheeler
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Re: Immobiliser with keypad on XUD

Post by wheeler »

wennbom wrote:
28 Dec 2021, 10:17
No, I have not checked at the fuel injectors but I can hear the solenoid pull and there is fuel in the plunger seat.
Is it as simple as disconnecting one of the injectors and crank the engine?
You should loosen the injector pipe nuts (at the injector end) a few turns, do this with all 4 injectors at the same time. This should have been done anyway to bleed the air out of the pipes. Once you see fuel spitting out tighten up the pipes & try to start again. Does it have a hand primer too? If so get someone to pump this too as you try to start it.
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

Ok, got the engine running!
Silly embarrassing error by me - didn’t confirm that my ignition current also was live while cranking….

So now when that’s sorted I wonder if I could retain the Bitron relay, or if it’s better to run a new fuse and relay for the solenoid?
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

I’m confused again
Is the immobiliser also controlling something on pin #10? Like a ground relay or something.
I have got
12v permanent from battery on #11
12v ignition on #2

I can get 12v for a brief moment on #1 if I disconnect the battery for a minute or so and then reconnect it.
But the the keypad leds start lighting up and I only get 1.35v on #1
12v on #3 doesn’t help either.
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admiral51
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Re: Immobiliser with keypad on XUD

Post by admiral51 »

Have you got the keypad code assuming that it is still plugged in ?
If so i suppose you could go down the old school route with the keypad :)

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white exec
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Re: Immobiliser with keypad on XUD

Post by white exec »

If you want to retain the keypad in operational state, the Bitron double relay is essential.
If not, you can simply feed the engine stop solenoid with +12 when IGN is on (and while cranking!).
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

What I learned yesterday was that
11 - direct +12 from the battery
Isn’t actually from the battery.
It comes from somewhere else and can be manipulated by the immobiliser.
As soon as I connect my new single wire solenoid to #1 on the Bitron relay the supply voltage on #11 drops to 1.35V, and consequently the output on #1 is also 1.35V which is insufficient.

I made a new fused feed (on this car it’s less than 0.5m) directly from the battery to #11 as per Bitron instructions. Can runs and I use the Bitron double relay.
The keypad became useless the minute I replaced the original 3-wire solenoid.
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moizeau
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Re: Immobiliser with keypad on XUD

Post by moizeau »

When I swapped my 2 1/4 diesel, mechanically operated stop solenoid engine for the later 2 1/2 in my S111 I just ran an ignition feed to the solenoid so it turns on and off on the key. It also has a BX glow plug relay. :-D
wheeler
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Re: Immobiliser with keypad on XUD

Post by wheeler »

wennbom wrote:
01 Jan 2022, 12:57
Ok, got the engine running!
Silly embarrassing error by me - didn’t confirm that my ignition current also was live while cranking….
wennbom wrote:
27 Dec 2021, 11:54
Tried feeding the solenoid directly from the battery - plunger lift and there is fuel - but it won't start.
I never thought to mention about the live dropping out on crank as you said you tried feeding the solenoid direct from the battery?
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wennbom
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Re: Immobiliser with keypad on XUD

Post by wennbom »

Yes, my mind was playing games with me.
I was 100% certain I had tried to feed it directly from the battery. Clearly I hadn’t and that sent me off trying to find an error that didn’t exist.
I also unfortunately involved you guys as well and consumed your time. Sorry about that.

The engine now runs good and I can move on to the next challenge of finding the cause of the non working rev counter.
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white exec
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Re: Immobiliser with keypad on XUD

Post by white exec »

Try renewing the sensor on the flywheel (or checking its connections, and that it meters up with a resistance). They do give up.