Agree with
@Mike in AZ too much parasitic draw.
With some basic meter usage skills and decent auto ranging multi-meter you can easily check/find a parasitic draw.
First -- I am glad to see you are checking fuses with a test light!
However a blown fuse would most likely NOT be the cause of a parasitic draw.
But to answer your question regarding the fuses you mentioned
Fuse 5 is crank fuse - it will only have voltage when key is in crank position
#7&8 are for headlights - they have to be on for voltage reading
#17&18 are stop/turn lights - again they have to be turned on to check the fuses
There are other fuses that will have the same results in the rear fuse box.
If you have a
decent voltmeter that has a mili volt setting -- checking to find out which circuit has an excessive draw is fairly easy.
First turn everything off -- open passenger door so you will have access to the rear fuse box and then latch door while it is open using a pocket screwdriver or similar BE SURE NOT TO FORGET TO UNLATCH BEFORE TRYONG TO CLOSE WHEN DONE --- Pull up on handle - you might have to use pocket screw drive to help latch open up while you lift on handle
Then measure voltage drop across each fuse -- I have a attached a good you tube video showing and explaining this method
THIS METHOD WORKS. I have used it at work and helped another member find a bad instrument cluster using this method last year !!!!!
Please watch the entire video -- over 10 minutes and then reply if you have any questions before you perform the testing, Incidentally - the video says to wait one hour for all modules to go to sleep -- on yours the modules should power down (go to sleep) in about 15 minutes.
Once you determine which fuse (circuit) has the fault we can work from there. You would also know what fuse to pull when it is parked until you get it fixed. You could also verify you found the problem this way - pull the fuse park overnight and then recheck battery voltage in the morning. BE SURE TO TEST ALL FUSES, DO NOT STOP at the first one that gives you a reading.
The average rule of thumb on an old car like ours is 50mA or 0.50 Amps.
You can also email me if you have questions --
Autoprof1960@gmail.com