question for adrian
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From: Parafield Gardens
Dear Jim,
That would have been handy to know earlier. The PDAS/ABS control unit is provided with over voltage protection through relay R34. Yes voltage spikes will really upset the control unit and other units as well.
I recommend removal of the alternator and regulator assembly immediately.
We will never be able to fix this problem until the alternator and electrical generation system is fixed.
Ciao,
Adrian
964C4
That would have been handy to know earlier. The PDAS/ABS control unit is provided with over voltage protection through relay R34. Yes voltage spikes will really upset the control unit and other units as well.
I recommend removal of the alternator and regulator assembly immediately.
We will never be able to fix this problem until the alternator and electrical generation system is fixed.
Ciao,
Adrian
964C4
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 934
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From: charlotte nc
I had been monitoring the red/grey wire from the r34 relay but when the light came on there was no interuption in votage. I also had a mic attached to the relay to listen for the click while driving. No brake in voltage, and no click was heard. Also when the light came on there was no voltage spike. My meter also has memory so even if I missed it while driving it should have been recorded. Don't get aggrivated. Give me some time to ck the sensor more and I'll post back.Thanks again, Jim
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From: Parafield Gardens
Dear Jim,
How you fix the problem is up to you. I am not upset I am only tryng to help.
If you have a system which is suspected of voltage spiking you need to fix that first. This suggests a regulator shorting out.
I am a one problem at a time guy. It is possible that the control unit is now damaged and that is a concern.
Have you confirmed the voltage spiking? and what what the highest recorded value? You normally will feel a spike through the engine as the alternator tries to stall it. I remember my old 924 spiking to 18V or so and the engine used to really bog down. A new alternator/regulator fixed this problem.
Ciao,
Adrian
964C4
How you fix the problem is up to you. I am not upset I am only tryng to help.
If you have a system which is suspected of voltage spiking you need to fix that first. This suggests a regulator shorting out.
I am a one problem at a time guy. It is possible that the control unit is now damaged and that is a concern.
Have you confirmed the voltage spiking? and what what the highest recorded value? You normally will feel a spike through the engine as the alternator tries to stall it. I remember my old 924 spiking to 18V or so and the engine used to really bog down. A new alternator/regulator fixed this problem.
Ciao,
Adrian
964C4
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 934
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From: charlotte nc
I have not witnessed a spike but have been monitoring the voltage. I was also concerned about the control unit so I tested it in a known good car with no problem. I was only able to test it for 25 minutes But if I Need to test it longer the other cust is also a good friend and will alow me to do so. I also installed a new batt to body ground because the original one looked ugly. Thank you for you patiecne
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From: Parafield Gardens
Dear Jim,
Please do not worry about my patience it would be the customer I would be worrying about.
Eliminating the control unit is a good idea. I still suspect the accelerometer.
Maybe you could borrow this as well and give it a try.
Ciao,
Adrian
964C4
Please do not worry about my patience it would be the customer I would be worrying about.
Eliminating the control unit is a good idea. I still suspect the accelerometer.
Maybe you could borrow this as well and give it a try.
Ciao,
Adrian
964C4
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Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 934
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From: charlotte nc
Adrian, I did have the voltmeter hooked up when the light came on while driving as stated before. However, this no charge at start up is happening more frequently. I agree with you on the whole voltage issue and will be correcting that before anymore tests are done. Thank you and if anything else significant goes on I will let you know. Also I will be visiting Barnes and Noble for your book!
