[quote author=cruiserdan link=board=2;threadid=14475;start=msg136438#msg136438 date=1081613651]
OK.
So where does the voltage originate and how would one address it if present? That would certainly offer an explanation as to why some vehicles have more than others. (Guess what I'm gonna do next
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Hi folks, I was away for awhile and saw this super thread. I am interested in following all the thought and theory out there on this subject. Also, I am indeed interested in the group purchase plan for laboratory analysis, is there an ante as such, if not maybe we should work out what the total would be, then see how many others may want to participate. Super cool thread!
Anyway, the voltage originates from two or three types of electrolytic reactions. I found something I felt I should share with you folks, it explains exceptionally well the ways this process occurs. Hope this helps.
Electrolysis occurs in our cooling systems in two or three ways. One of these ways is that stray electrical current from several operating systems in the vehicle flows to the cooling system. As the coolant flows to then throughout the system it develops a minor electrical charge (less than .3 volts). Once this stray electrical current finds its way into the system, it travels around (even through the hoses) looking for a ground. When the ground is located, the electrical current is discharged, no harm done. But, what happens when there is no ground to be found, or an ungrounded electrical device in the vehicle creates excess electrical current? The cooling system has the ability to hold large amounts of excess electrical current, which turns the coolant into an electrolyte. Any fluid that becomes electrically charged (like automotive coolant) becomes an electrolyte. If the excess current cannot be discharged by means of a ground, it continuously travels through the system, looking for a way out. During its travels, the charged coolant causes electrochemical reactions with the various surfaces it contacts. When it locates an extremely favorable material, it goes to work to try to consume the material completely. Think of the charged coolant as a very hungry termite. Trapped in a box made of several different kinds of wood, it travels around inside the box, looking for a way out. As it goes along, it samples the various woods. When it finds the tastiest piece, it sets about consuming that piece until it can escape. The charged coolant does much the same thing, traveling around in the cooling system, looking for that “tasty” piece. When it locates it, it “eats” its way through trying to escape. Once the material is gone and once the coolant can escape the electrolysis process is over. Until the next favorable material found.
Another way electrolysis occurs is the passage of an electric current through a conducting solution that is then decomposed in the process. When a cathode, or negative electrode, and an anode, a positive electrode, are dipped into a solution and a direct current source is connected to the electrodes, the positive ions migrate to the negative electrode and the negative ions migrate to the positive electrode. At the positive electrode each positive ion gains an electron and becomes neutral; at the negative electrode each negative ion gives up an electron and becomes neutral. The migration of ions through the electrolyte constitutes the electric current flowing from one electrode to the other. Electrolysis can cause material surfaces to pit and flake. The most common effect however, is corrosion. We have all seen the white and green solder blooms in cooling systems. We have also all seen sediments settling in areas of the cooling system. Ever wonder what caused them? Electrolysis is one prime candidate.
Aluminum affected by electrolysis will corrode rapidly in the form of flakes. These flakes will suspend in the cooling system and eventually build up causing system failure. Cast iron engine components will corrode, causing rust to enter the system, contaminating the coolant and allowing the system to slowly destroy itself. Soldered joints can become flowable and can produce leaks. Premature part failures, overheating, cavitation of cylinders and passages, and deposits causing system failure can be symptoms of or can be caused by electrolysis.
How can you test for and correct electrolysis? The test is very simple. Using a volt ohm meter (digital is preferred) connect the black or ground lead to the battery ground and lower the red or positive lead into the coolant in the radiator. Do not touch the filler neck sides or the tank. Any reading over .3 voltage is indicative of excess current entering the cooling system. Always perform this test twice, once with the engine off and all accessories off and once with the engine running and common accessories (radio, heater or A/C, lights ect.) on.
The first and most important step in the correction of electrolysis is a good visual inspection. Check all under hood wiring for loose connections or poor repairs. Look for additional accessories, poor wiring, or poor grounds. Hopefully the problem is just a poor ground in the engine compartment. This is usually the problem, as many DIYers and technicians alike fail to reinstall engine ground straps. If the problem does not readily present itself, prepare for what may be a long diagnostic process. Inspect the wiring under throughout the vehicle, paying close attention to the grounds. If no bad wiring is located, have an assistant hook up an ohm/volt meter, turn every-thing off and read the voltage. If it is in acceptable limits, turn on the accessories one at a time. When you see a voltage spike, you have your culprit. Locate and fix the problem, but continue with the test to make sure there are no other electrical problems. If you record unacceptable voltage readings with everything turned off, go to the fuse panel and remove and reinstall the accessory fuses one at a time. When you get a voltage drop, note which accessory you disabled and check the wiring for that accessory. After making necessary repairs, reinstall the fuse and check the system again. If there is no excess voltage present, the job is complete. If there is still excess voltage, continue removing and reinstalling fuses one at a time and make necessary repairs. If there is still excess voltage, the electrolytic process is likely coming from a reaction with dissimilar metals in the cooling system itself, particularly aluminum. In this case, constant, careful preventive maintenance is recommened and required to prevent harmful amounts of deposits.
It was mounted on the firewall on the RH side in front of the A/C bulkhead fittings.
NO WAY did search pull it 
