Bosch Hall Effect Dizzy

[Guest tomottewell]

Hello, trying to muddle my way through a 'no spark' problem and just wondered if anyone knew how to test a bosch hall effect dizzy???? Joel mentioned something about using an led, i could just do with a bit more info??

Thanks Tom

[Guest Dan_Beeston]

If you've got a 12v LED you can probe in through the back of the connector (down the side of the wires) while it's plugged in. +ve side of LED to power, -ve to signal (middle pin). It should flash as the engine turns over. Alternatively +ve to signal, -ve to ground, same result.

 

Alternatively probe into the middle pin with a multimeter (with it connected). With the ignition on you should see it switching from 0V to 12V (relative to ground) as you slowly turn the engine over by hand (bear in mind it could possibly fire & kick, however unlikely, so take the coil lead off or summat)

[Guest salty_monk]

Don't forget to check voltage at the coil & change the rotor arm, those have been known to go duff too....

[Joel]

Joel mentioned something about using an led, i could just do with a bit more info??

 

Sorry Tom, if you're anything like me a picture will help

 

http://community.rhocar.org/index.php?show...24&hl=Dizzy

 

Third post down by 'Grim', there's a picture showing how to do what Dan describes above. And if you read on there's plenty of other info there which may help, as I was having the same problem.

 

What my problem turned out to be was the signal (centre pin on the dizzy connector) wire needs to be shielded, and mine wasn't. Don't know of that's the same on your setup though.

 

HTH

[Guest Dan_Beeston]

It wasn't so much the fact that your wasn't shielded Joel, it was the fact you had connected the shield to the signal line!

[Joel]

It wasn't so much the fact that your wasn't shielded Joel, it was the fact you had connected the shield to the signal line!

 

 

This explains a lot......if I can't even get the diagnosis correct, what chance for the actual wiring??

[Guest tomottewell]

thanks for that. i've looked at the link. is the top figure (21) talking about the plug that goes into the dizzy? what does cmp mean? thanks Tom

[Guest salty_monk]

crankshaft position sensor.

 

Dan

[Longboarder]

21 is a diagram of a hall effect CaMshaft Position sensor. The routine for testing any hall effect sensor is the same. Describes testing the harness first at the plug, in your case the plug that goes to the dizzy. Then describes testing the Hall sensor (dizzy) with the harness plugged in.

 

If you copy the pictures, right click and copy, then right click and paste them to your desktop they will be much clearer.

 

Nigel

[Guest tomottewell]

hello. i've tried the thing with the led and there is no flash. but there is also no power coming to the dizzy. i've also foung that when the manifold heater relay is shorted out there is a spark produced. any ideas?

Thanks Tom

[Bob Tucker]

and dance naked over the glowing embers.

 

Nigel,

please dont do this over the Stoneleigh barbecue......please.....please...please... :D

 

Bob