Hall Effect Resistance??

[yellowoctupus]

Since the hall effect sensor is essentially a coil and magnet which gets disrupted by the windowed distributor rotor, there should be a resistance check on the coil to see if it's still good, right? Does anyone know what that resistance should be?

 

[shadetree]

Since the hall effect sensor is essentially a coil and magnet which gets disrupted by the windowed distributor rotor, there should be a resistance check on the coil to see if it's still good, right? Does anyone know what that resistance should be?

A hall effect sensor is not a coil and a magnet. It is a solid state device, and there is no way to check the sensor reliably. Replacement is the best check.shady

www.mightyautoparts.com/pdf/articles/tt64.pdf

 

[yellowoctupus]

Good call Shady. I'm glad I didn't waste my time trying to pull the distributor to measure the resistance on that unit (and toss 9V from my meter into the semiconductor too!). I read about the crankshaft pos. sensors going bad and causing misses in that article, could this sensor just blank out entirely sometimes? I either have plenty of nice spark or nothing at all. Could that be because my sensor is sending out too weak of a signal? I can measure the amplitude of the signal on a scope if anyone knows what it Should be.

 

[shadetree]

Like all electronic devices, it can do crazy things at any time. I don't think the device would get weak, it simply works or it doesn't, or does so intermittently. If it is suspect, sub a known good one to know for sure.

It should put out a square wave, and the pulse should be close to supply voltage. You can sometimes check forever, and never see a problem, put them back on the vehicle, and they fail in minutesl.shady

 

[IRKillroy]

the gap is very important too...

if you have a dirty cog, or a tooth is chipped will mess up your signal sporadically too.

you should also make sure you have batter voltage going TO the sensor... if that power is intermittent then your computer will think the engine isn't spinning.

as they said a hall sensor only tell the computer when metal is in front of it... then it's wide open... when there isn't is completely shut... or vice versa when using electrical terminology.

 

[yellowoctupus]

I'll have to check tomorrow on the supply and output voltages it's got going. I double checked the TFI worksheet in the Tech library, and it said you should see out a the spout connector 5-7 Volts which makes sense. BUT, since you're supposed to set the static timing with the spout connector disconnected, how does it still get spark? Wouldn't the computer think the engine's not turning over? Or is there still some signal going to the computer?