Hall Sensor up close
 

85' 245 DL LH 2.2 - briefly, new hall sensor fixed the no spark, but not for long. Pulled and repaired ignition harness and main harness (6 bad potential shorting sites throughout), cleaned all grounds (!) and car ran great for a month. Now it won't start again and I'm suspecting the hall sensor again (same symptoms, no spark, no second click in FPR). My hopeful thinking is that the period of running/diagnosing with a bad harness significantly shortened the life of the new hall sensor.

My question is two fold:

1. I'm curious about what specifically might cause a sensor to inflame or crack like these two (the left one replaced the right one):

Attachment 25830Attachment 25831Attachment 25832Attachment 25833

2. Also could anyone explain how to check the voltage/ohms of the 3 pole connector to the hall sensor and what I should be reading at each pole with ignition on then cranking/running (assuming I were to back probe the connector/wires)? Or otherwise how to determine if the correct amount of current is flowing through the sensor? I'd like to check this as soon as I get the new sensor in hopes that I don't fry another one...

Attachment 25829

UPDATE (FIXED):
I'll describe the process as best and brief as possible. Obviously the root problem was the faulty plastic on the wires in the ignition harness and main harness. Electrical shorts had caused the Hall Sensor AND the ICU to fail. I did my best to diagnose what was wrong, but ended up replacing the hall sensor first, this worked for a short while. I then pulled the harness and replaced a few bad wires. The car ran for about a week, then failed again. The ICU kept coming up as a possible fault. So I replaced it with another used one, and BINGO I have since put about 50,000km on the car :) it is now at 430,000km. plenty of life left with easy daily driving

the hall sensor signal is a differential very low current thing with almost no voltage, like thousandths. the only way you'd see anything there would be with an oscilloscope set for differential mode on the + and - signals with a very high impedance at the scope probes, and you'd probably just see a few millivolts.

Hall sender issue?
 

I am to the forum. How did you resolve it????


[​​​​​QUOTE=Parc;459732]85' 245 DL LH 2.2 - briefly, new hall sensor fixed the no spark, but not for long. Pulled and repaired ignition harness and main harness (6 bad potential shorting sites throughout), cleaned all grounds (!) and car ran great for a month. Now it won't start again and I'm suspecting the hall sensor again (same symptoms, no spark, no second click in FPR). My hopeful thinking is that the period of running/diagnosing with a bad harness significantly shortened the life of the new hall sensor.

My question is two fold:

1. I'm curious about what specifically might cause a sensor to inflame or crack like these two (the left one replaced the right one):

Attachment 25830Attachment 25831Attachment 25832Attachment 25833

2. Also could anyone explain how to check the voltage/ohms of the 3 pole connector to the hall sensor and what I should be reading at each pole with ignition on then cranking/running (assuming I were to back probe the connector/wires)? Or otherwise how to determine if the correct amount of current is flowing through the sensor? I'd like to check this as soon as I get the new sensor in hopes that I don't fry another one...

Attachment 25829[/QUOTE]