Hall Sensors - I think

[Northdowns]

Hi all.
After the last couple of weeks of bad weather, I've not used the bike, it was running well before. Dragged it out Saturday to check over, clean etc etc - it wouldn't start.
I started to check a few basic's and quickly concluded - no spark.
I've checked the coil, and ecu, popped these off and checked on a mates R1100S, (the map might have been wrong for his bike, but it started and ran OK).
I then turned my attention to the Hall Sensors, as these seem to come in for a lot of stick.
I've jury rigged the supply and ground, and manually turning the engine over measured the signal o/p voltage, this dropped from 12.7v to 2.6v as I passed TDC. All the tests say use an LED, but 2.6v would keep an LED alight?? (not sure) but as I don't have one, and I have a very nice FLUKE DVM, I thought I would just measure the voltages!

Anyway, the nice people at Motorworks are sending me a secondhand unit to test.#

But has anyone else any experiance of testing Hall Sensors?

Any help or advice recevied......

John

[boxermania]

Northdowns,

You didn't mention what model bike you have, a two plug or 4 four plug as there could be a diferent issue with the 4 plug, but first an answer to your question. The Hall Effect Sensor is effectively a square wave switch. Based on your findings it's high at battery voltage, 12 V and low at 2.6 V so it appears to me that one of the two is working, need to check the other one. I have included a little info for your edification.

http://en.wikipedia.org/wiki/Hall_effect

http://www.wellsmfgcorp.com/pdf/Counterpoint3_1.pdf

BTW, in the case that one or more of the HET are bad, you don't have to buy the expensive BMW variants as the only thing diferent from the garden variety ones are the connectors and you can splice the connectors to the new HET(S). The HET(S) can be had for $6 or $7 stateside.

On the other hand, if your bike is a 4 plug (sparking plug that is) they have had some issues with heat affecting the coils.....of the primary with something similar to what you are being faced. You might want to check that as well.....

Best of luck and keep us posted........

[Northdowns]

Boxamania,

Cheers for your info, and sorry for not qualifying what bike I have, its a 2001 single spark model, and interestingly, its the sensor shown on the wiring diagrams as S1 (orange wire) that drops, the S2 o/p (Black Wire) stays permanently at 12.?V.
Motorworks are shipping me a 2nd hand pick up unit on sale or return, should be with me Wednesday.

Cheers for the additional info.

Regards

John

[boxermania]

John,

If the sensor doesn't switch voltage as it passes the trigger, would be an indicaton that it's bad. The voltage drop is deected by the ECU as the signal for the spark.

You have one coming and you are on the right track with the testing......as far as I can tell.

[Northdowns]

New pickups arrived today (Cheers MotorWorks), but before fitting, I tested them first, when switching, the 'new' ones drop the signal volts to a few millivolts, where as the unit on the bike, the top sensor drops to around 2.7v and the lower remains at battery volts - Knackered.

Replacement unit fitted, checked timing, fired up first time and running sweet.

Thanks to boxermania for your thoughts and advice.

It dark and its raining, but I might just go out for a ride anyway........I've missed my bike, what with the Ice, then the Pickup issue, its been over two weeks....

Happy Days

John

[CycleRob]

Northdowns. Kudos and well done . . . . to your diagnostic talents and repair abilities. Privileged you are for owning a FLUKE DVM. I've used their premium test equipment when I worked for an aircraft engine mfgr 17 years ago.

You've also given us a quick test method for diagnosing questionable Hall sensors.

Things weren't too bad for you during the OilHead's downtime, seeing as you also ride an SV-650. In my case, my other bike is an 18 speed 26" mountain bike and the roads here all have zero shoulder width.

[Northdowns]

Hi CycleRob,

To be honest, the SV is my wifes, and its her toy, and with the amount or road salt on our roads at the moment, she's not letting it out of the garage. So it's been quite frustrating.

We also have a couple of MTB's in the garage for sunny days out, a couple of retro ProFlex's (me an 857, and my wife an 855), they do get quite a bit of attention due to the unusual fork arrangement. Very forward thinking at the time. Its a similar story with the 1150R, you can see the front suspension, perhaps its the use of alternative thinking to resolve old problems....

Anyway thanks for the nice comments, and I hope the info will be useful.

Cheers

John