Scorpion 738 alarm

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flippin'eck
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Scorpion 738 alarm

Post by flippin'eck »

Trying to get some info on the 'Scorpion 738' alarm that came fitted on my mk1.

It says '1988' [corrected ;)] on a sticker on it - since my mk1's a 1989 car, was wondering if this alarm might have been commonly fitted from new, and maybe other owners might have a wiring diagram etc.

Managed to get it working ok by twiddling the variable capacitor in the keyfob - the frequency must have drifted over the years; when I got it you had to hold it right near the car but now it'll work from a good distance.

Problems remaining are that the indicators don't flash to signal arming / disarming, and also I was wondering what the adjuster knob on the back of the alarm box does. I noticed a receipt in amongst the history for 'disconnect flasher circuit'.. maybe this is a clue.

Anyone have any info or ideas?
Last edited by flippin'eck on Sun Oct 29, 2006 11:27 pm, edited 1 time in total.
jimi
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Re: Scorpion 738 alarm

Post by jimi »

flippin'eck wrote:
It says '1998' on a sticker on it - since my mk1's a 1989 car, was wondering if this alarm might have been commonly fitted from new

:? :?
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flippin'eck
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Re: Scorpion 738 alarm

Post by flippin'eck »

Well spotted :oops:

it says 1988 not 1998 :mrgreen:
jimi
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Re: Scorpion 738 alarm

Post by jimi »

:lol: :lol:
I think Scorpions were a pretty standard fit, I 'm sure mine originally had a Scorpion, but I have no info on them at all, sorry
Jimi
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kevin..in
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Re: Scorpion 738 alarm

Post by kevin..in »

mines got one fitted but no remote
I have though never used it as no one ever takes any notice of car alarms and one of this vintage could easily be bypassed by a newborn council estate kid :?
superbad
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Re: Scorpion 738 alarm

Post by superbad »

I took mine out as it was disabled and had no keyfob. I think they were a dealer-fitted option.

Btw, Does anyone else have an LED in their dash blanking plate? Mine was snipped off at the wire behind - thought it must have been something to do with the alarm?

Image

ps, I've got a coin holder now :wink:
andyj
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Re: Scorpion 738 alarm

Post by andyj »

One of my key fob transmitters for my Scorpion alarm stopped working and couldn't be retuned. Like you it started only working from close range then packed up altogether. So be careful or get caught away from home and not being able to disarm it! Mr T supplied new one for £35 (that was a couple of years ago). Worked fine with that one.

I never had a key to switch off unit and was bit worried about at but fortunately I had the model without battery back up in alarm unit itself so simply went off if power disconnected.
flippin'eck
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Re: Scorpion 738 alarm

Post by flippin'eck »

Kevin.. yeah I'd figured it'd probably be about as useful as you say. I figure if it was fitted from new by a Toyota dealer it might be worth keeping purely from a nostalgic quasi-authenticity standpoint, otherwise I'd probably change it if I started leaving it in dodgy places


One of my key fob transmitters for my Scorpion alarm stopped working and couldn't be retuned. Like you it started only working from close range then packed up altogether. So be careful or get caught away from home and not being able to disarm it! Mr T supplied new one for £35 (that was a couple of years ago). Worked fine with that one.


Don't know if it might have been a similar problem on yours Andy but mine needed a few joints resoldering on the circuit board in addition to twiddling the adjuster. Think I was lucky not to fry the chips.

Also, 'twiddle - try - twiddle - try - twiddle..' didn't work, I had to do 'hold button down, keep twiddling until alarm picked up the signal' if you see what I mean. It seems to be a really fine adjustment. No idea what that adjuster actually changes (frequency it transmits on, signal strength, something else) just that it seemed to do the trick here.
kaiowas
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Re: Scorpion 738 alarm

Post by kaiowas »

I've got some sort of alarm on mine as well as a bag full of remotes and keys that came with it. I really should get around to investigating them all at some point and finding out if any of them still do anything.
kevin..in
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Re: Scorpion 738 alarm

Post by kevin..in »

superbad wrote:I took mine out as it was disabled and had no keyfob. I think they were a dealer-fitted option.

Btw, Does anyone else have an LED in their dash blanking plate? Mine was snipped off at the wire behind - thought it must have been something to do with the alarm?

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ps, I've got a coin holder now :wink:

almost certainly something to do with either an alarm or immobiliser that has been disconnected in the past
kaiowas
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Re: Scorpion 738 alarm

Post by kaiowas »

Just got around to playing with my bag of keys and remotes. It looks like I now have some sort of functioning alarm.

I can arm and disarm it from the remote although I haven't tried opening the door with it armed yet for fear of upsetting the neighbours. Besides, I know for a fact that I'll totally forget about it in the morning and open the car as normal anyway!

Bit disappointed that it doesn't operate the central locking (this would be of more use to me than the alarm itself!) as I know from the last time I took the door card off that there's some sort of extra wiring in the doors. I've also got no idea whether it's just an alarm or whether it has any kind of immobiliser built in. (I doubt it on something so old)

The writing on the main unit seems to suggest it's a Scorpion 737 although google doesn't turn up anything useful and there's no mention of the alarm amongst my pile of papaerwork that came with the car.
flippin'eck
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Re: Scorpion 738 alarm

Post by flippin'eck »

I've emailed scorpion alarms to enquire about documentation on both the '737' and '738' systems, will let you know what does or doesn't come back..
kaiowas
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Re: Scorpion 738 alarm

Post by kaiowas »

I did find some online documentation on the '838' system last night. From the text and diagrams it doesn't sound too disimilar to what I have although I've not had a chance to compare my wiring with the diagrams yet.

Probably best to download these as they're not on the scorpion site any more, I had to use an internet archive to find them again:

User guide:
http://web.archive.org/web/200204022133 ... 38user.pdf

Fitting Instructions
http://web.archive.org/web/200204022133 ... itting.pdf
un1eash
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Re: Scorpion 738 alarm

Post by un1eash »

My car has a 738 fitted, so do a few other mk1's i know. I need a new keyfob as mine is abit battered. You can get replacments from most alarm fitters, cost aournd 35-40 pound. I couldnt live without remote central locking.

ps. the knob on the back is the sensitivity. They also came with a key so you can disarm the alarm when the cars not in use for long periods.
flippin'eck
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Re: Scorpion 738 alarm

Post by flippin'eck »

Oh that's what that strange key is on my keyring :mrgreen: nice one - was wondering about that.

Nothing back from my email yet but those links look useful. Will go & have a read :)
davidb
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Re: Scorpion 738 alarm

Post by davidb »

A bit of a thread resurrection - I had a Scorpion alarm in my MR2 when I bought it in 2012. Everything worked - alarm and central locking, until one day I welded a new arch panel, with the battery connected and it never engaged after that. It does still work, but the remote won't speak to the alarm so maybe the transmitter is gone. I still have the little key so disabled it, but the proximity alarm is still very active in the cabin (and has killed a couple of batteries over the years).

Does anyone know if these are easy to reprogram, or does anyone want to sell me the red siren unit and a fob? I thought it worked perfectly as an alarm system.

They worked on 418Mhz, and also came on Mercedes, Land Rovers and Fords.
un1eash
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Re: Scorpion 738 alarm

Post by un1eash »

I ended up replacing my alarm with a Falcon Predator Evo3 pager alarm as it was easier and cheaper then trying to find replacements for the Scorpion alarm.
boondougal
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Re: Scorpion 738 alarm

Post by boondougal »

My alarm ended up here:

Image

It was an aftermarket figment and although it did originally work when i got the car it was a mess or an install and started to get temperamental.

Will be looking at other options once the car is back not he road later this year.,
jimi
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Re: Scorpion 738 alarm

Post by jimi »

boondougal wrote:

It was an aftermarket figment and although it did originally work when i got the car it was a mess or an install and started to get temperamental.

Maybe it just imagined it was an alarm :lol:
boondougal
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Re: Scorpion 738 alarm

Post by boondougal »

jimi wrote:
boondougal wrote:

It was an aftermarket figment and although it did originally work when i got the car it was a mess or an install and started to get temperamental.

Maybe it just imagined it was an alarm :lol:


Lol... just like i imagine i can touch type!!!!
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