Battery died while driving

[Austin Gillespie]

So I just replaced the battery this past week and charged it all up before going out for a drive today, and about 35 minutes into my drive, the car just totally died, luckily I was in a spot I could coast off the road. The car would not start back up, accessories came to life briefly when I turned the key but it totally died just after that. I've been having some parasitic drain while the car is off, but it's never died on me while driving like that. Any ideas as to what could be the issue here?

[Ian Linden]

Charge the battery, then put a voltmeter across the battery. See whether, with the engine running, the voltage is greater than with the engine off. If not, the alternator is not charging.

If that's ok, disconnect the negative lead and put an ammeter between the negative post and the negative lead. Read the current drain. Now pull fuses one at a time, until the drain stops/ reduces appreciably. The last fuse pulled will tell you the circuit causing the drain. Unfortunately, our wiring diagram is for an EA11R, so there may be some differences, but you should use it as a guide to identify the cause of the drain. Note that some circuits may not be fused. e.g. the windows use a circuit breaker.

If you don't get anywhere with that, the drain may be in the wiring upstream of the fuses, so look for chafing/insulation damage on the harnesses.

[Austin Gillespie]

It looks like the alternator isn't charging. Parasitic drain was annoying but that's gone to the back of the list as I now can't drive more than 15 minutes with a freshly charged battery before being dead in my tracks. The fuse isn't blown so is there something else I should check before looking into a new alternator? Taking it into the electrical shop tomorrow and bringing them the wiring diagram and electrical pages from the EA21R manual but any additional knowledge to be armed with would help. Thanks Ian you're a godsend

[Ian Linden]

Provided you can find a shop which has someone willing to get into it, you probably won't need a new alternator. Chapter 6H gives full information for overhauling the alternator, but the most likely problem is the brushes - Page 6H-12.

Btw, parasitic drain is not unknown in cars of this age, and the easiest way to address it is to disconnect the battery when not in use. Something like this is ideal for the Cappo, because the ECU does not rely on battery power to retain stored values. You may lose stored radio staion tuning, though. Try to get the type for the smaller diameter battery posts used by the Cappo, but if you can't, adapters are available.

[Ian Linden]

.... pages from the EA21R manual....

You have an EA21R manual, or is it a typo?

[Austin Gillespie]

Typo my bad. I only have the EA11R English manual but gave that to the shop. It seems to be the alternator so I've ordered a fresh one from Japan as the alternator rebuilding guy couldn't source a fresh voltage regulator.

[Murray Betts]

Sorry this is a bit late......
remember that the fog light relay is attached to a permanent supply and if you accidentally press the fog light switch it will power up the relay even when the ignition is off. The current draw of the relay coil is enough to flatten a battery in a relatively short time, a couple of weeks or so anyway. If you are not using the car regularly this can kill a battery, my original one died in exactly this way when I was working away for a month.
I guess the fog power was done this way for regulations, being able to have the fog light on without ignition for safety reasons.

[Janet Naylor]

This happened to me yesterday - thank you to everyone who has posted about this - I'm hoping that it's not too serious....