intermittent ABS light problem solved 98 CRV

I have had the ABS light come on and stay on for several days at a time. This has been going on for a couple of years.
My mechanic would check the error codes each time and find different
errors. He went through and checked every part of the braking system and could find no fault.
I did a very extensive google search for this problem. One person's description of his problem jumped out at me. On the highway as he would slow down to a stop, his headlights would jump up in brightness. Mine did this too.
I have two way radio gear that draws up to 20 amps and accessory fog lights. It was hooked directly to the battery as recommended by the radio manufacturer. This method produces the least alternator whine. However, when you do this, you and I are bypassing the load sensor for the 12 volt power. This then draws down the battery as you drive. As you slow down and the alternator is less able to supply voltage there is a sensor in the computer that basically says holy crap the voltage is way too low and snaps the alternator charger to max. This produces a very sharp spike in the 12 volt line that triggers errors in the ABS computer.
This was easily solved by moving my accessory 12 volts loads from the battery to the other side of the load sensor. No problem since doing this. It is has now been 6 months.
My Honda is a 98 CRV.
It is certainly easy to add 12 volt power accessories to the battery, but don't do it. Go to the manual and find the terminal to use on the load side of the power sensor. On my 98 CRV this was easy. The terminal is next to the battery. This is important for fog lights and perhaps new xenon gas headlights.
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Reader wrote:

Good info!
Yes, "step one" in diagnosing odd and intermittent electrical/computer faults is to remove all the extra crap that's not supposed to be there.
Most of the time, for me, the owner doesn't even know the fffd-up wiring is on the car, since the previous owner, or a "friend" did it.
GW
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