Hall Effect sensor tester

[DanHoug]

here's a nifty little tester that will tell you if the Hall Effect sensor in your distributor is functioning. this can be done on the bench or with the dist installed in the engine. the schematic is not mine, robbed from the BMW airhead forums as they use the same Hall sensor in the 'BMW Beancan'. but this particular schematic is well designed and has a low current draw that will not burn out the Hall sensor. it's simple... just plug into the distributor and turn the shaft. it is self powered so if the sensor is good, the LED lights and extinguishes as the vane windows block the sensor.

i assembled the unit in a pen barrel and it is a great thing to have in the road box for troubleshooting.

Tricky Bits:
- the VW distributor plug is part number: 052905327 they are available on eBay but i have a stash of my own.

- the plug comes without pins. it uses an open barrel pin, requiring an open barrel crimper and the style from TE Connectivity is called "Connector socket 15-20AWG Crimp" MFG pn 925590-2. Digikey has them, PN A107135CT-ND. one CAN fold the flags over onto the wire with a pliers if you don't have the open barrel crimper.

- the schematic references a 12 volt diode and you MUST use a 12 volt LED or a regular LED with a dropping resistor. if you use a regular LED without a dropping resistor, you WILL ruin your Hall sensor!!!

- the 10k resistor in the schematic is a 'pull up' resistor to bias the sensor with some voltage. this was added by the author because spec sheets on Hall sensors request it and i like this attention to detail. it is NOT a dropping resistor for the LED!!!

here it is in action:

Link

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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[Gruppe B]

You know that many of us would buy this if it were available..

[DanHoug]

yah but... now you have the Secret to the Sauce so you can roll yer own!

it would sorta terrify me to a) charge what i think my spare time is worth as these are a little fiddly to make, and b) try to sell something that people wouldn't gripe about.

much prefer to provide detailed enough info that folks can just do it themselves as the construction is dirt simple if you have rudimentary soldering skills (or want to learn).
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[Vanagon Nut]

I just went outside to check my parts collection. The mk3 2.0 ABA engine uses the same looking distributor connector as the 2.1 WBX. Maybe other older vw's do as well?

Neil.
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1981 Westy DIY 15º ABA

1988 West DIY 50º ABA

VE7TBN

[DanHoug]

i think the connector is used on a large number of VW, Audi, BMW, Volvo, Saab, Porsche, etc Hall distributors. the key in shopping for them is to NOT buy the similar looking "EV TPS" connector.

i bought a bag of 25 of the genuine VW ones that were being cleared out. eBay vendors list both VW and aftermarket ones.
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[zimflux]

Is there an updated part number for the plug? Seems mine is different than the later models...

https://photos.app.goo.gl/kN9i1apKUpAPJyXSA

Thanks.
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84 1.9 Westy

[DanHoug]

the contacts you show are the same style, it just seems to be missing the wire retention bail and housing. just guessing but the PN i listed would possibly work.
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[jsalkeld]

Thanks for the secrete sauce! Someone has to ask the stupid questions. Usually those of us that know enough to be dangerous . . .

The resistor is a 10k ohm is a 10kOhm? I don't need to find a "pullup" ve "pull down"?

Is it placed in the circuit in a particular direction?
Is there a certain wattage? I have choices.


Thanks again
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86 "The" Westy
78 Super Beetle Cabriolet WIP
89 Porsche 911 Carrera Cabriolet - Summer Driver
85 Doka WIP

[ALIKA T3]

[Abscate]

No directionality in a resistor, it goes both ways 🏳️‍🌈

Current flow is minimal, a 1 watt rated resistors will work fine with 10x margin

10k is indeed 10,000 Ohms or 10 kOhm. It is customary to omit the ohms when discussin resistors in the trade.

They are described with three parameters, the resistance they provide to a circuit, the safe power they can dissipate, and the tolerance or precision of the resistance value.

Watch out for 24 Ohm Snakes….
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.ssS!

[djkeev]

How have I never seen this thread?!?

Come on Dan...... make me one? Pleeeeeeeease..........

I'm going to sticky this thread.
I put it under Ignition, though it could go in fuel injection too for it controls both......
Edit
I just put it in the Fuel Injection manual section under tools too.

Dave
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Stop Dead Photo Links how to post photos

Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473

Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537

Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert

[jsalkeld]

Thanks Abscate!
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86 "The" Westy
78 Super Beetle Cabriolet WIP
89 Porsche 911 Carrera Cabriolet - Summer Driver
85 Doka WIP

[Abscate]

Pullup refers the function of the resistor, not its type...when you get to my age though, its called Depends.
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.ssS!

[jsalkeld]

[DuncanS]

https://www.amazon.com/dp/B094YNNCC2/ref=sspa_dk_detail_0?psc=1&pd

These are prewired with the appropriate resistor. All you need with this is a battery.

Or https://www.amazon.com/dp/B08G4XCQSW/ref=sspa_dk_detail_4?psc=1&pd_rd

Duncan

[djkeev]

[jsalkeld]

[djkeev]

Check VanCafe
_________________
Stop Dead Photo Links how to post photos

Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473

Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537

Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert

[Vana Guy]

That is a very useful tool indeed. Simple to build and use.

For those interested in more info about their electrical systems, I have been thinking about putting together a small guide on how to use the popular DSO Shell scope to trouble shoot various digital systems and signals on the Vanagon.
They can be had for less than $50.00 assembled or less in kit form from eBay or Amazon, and can show a pulse width, amplitude, frequency, etc.. Good for Hall Effect signal, injector signals, coil signal...

[DuncanS]