Hey again guys, could use some help with an electrical problem. Sister was driving 89 accord LX carb AT yesterday and one of the heater hoses blew up. It was the 'P' shape one right above the alternator. I just finished replacing that and filling coolent, but now no lights come on in the dash in the run position and no crank in start position. (I guess, some of the leaking coolent dripped onto the Alt and shorted something) Also power windows will not move which is bad because they were left down. Cabin dome light does turn on. I checked both fuse boxes: the inside one was fine ; the under hood one had 3 blown fuses, 'BATTERY' (70A), 'LIGHT' (40A) and 'fog lamp'(15A). I replaced them all, (but currently the 70A BATTERY one only has a 60A fuse because the parts store did not have the correct one, will correct when I can). Replacing them did not fix the no-ignition / light/start issues. Any insight where I could check next? As a stopgap is there a way to override just for the windows so that I could roll them up?

Thanks for reading!

 

Check the fuses again to see if any of the new fuses are blown.

 

Hey guys, my bad. It seems that somehow the screws which hold the fuses in were corroded, and after cleaning everything up things are working again. Will replace the 60A with 70A once it comes in.

 

Thanks for posting the solution. Too often, we don't hear about the final solution.

For others that will read this thread, using a lower amp fuse is better for the wiring if you get a surge. Using a higher amp fuse risks damaging the wiring due to excessive current/heat. You only risk blowing a lower rated fuse at "normal" amps. Replacing a fuse is much easier than tracking down damaged wiring in the harness.

 

Hey Guys,

Reviving this thread because its not that old and the above story in the first post may be relevant.

A few months down the road now the charge on the car has ran out a few times where I had to jump start it and accessories started to go wonky while driving. This whole time the battery light has come on and off randomly while driving. (seemingly no correlation to RPM or at least the effect is delayed) Anyway I now get ~12.5V at the battery with no accessories on at idle, and ~13.5V by revving to ~3k rpm. This will not provide a good charge, and the voltage is likely lower when in gear.

I also have some doubt about the wire harness to the alternator - I followed the steps on page 24-21 in the manual - the charge warning light does NOT come on by turning the key to 'on'. I tried shorting the blue/white wire as it said to ground, but still no light, so there may be a problem with this connector wiring somewhere.

I am thinking the problem is either with this harness or with the reman alternator, is there a good way to tell, or any other suggestion I could try?

Thank you for reading!

 

Start with the simple stuff first.

Unplug the small connector to the alternator. Turn the key to the II position.

Check that the white/blue and the blue/yellow wires have battery voltage to ground. Use the - battery post as your ground for your volt meter.

 

Ok, slight update from your suggestion:

Both of the other wires on the alternator harness are correctly at battery voltage while key is on.

I also ran a second thick wire from the alternator positive post directly to the positive battery terminal, this made no difference.

I also tried some other experiment: with car on, disconnecting negative cable. In this case the car continues to run but the rpm dropped a bit. When I check voltage between negative cable (disconnected) and positive post with car on, I get the correct 14.4-14.6 volts, as soon as I connect the cable back to battery voltage drops down to 13 again (alternator can't keep up with load?) I can try yet another alternator if anyone thinks that would help, but I find it strange that I got low voltage on old and new alternator now...

Thanks for reading.

 

Not sure what you mean by this? Did the wht/blu and blu/yel wires have battery voltage?

The battery voltage issue could be the battery, the battery cables, or the alternator. I'd suggest disconnecting the battery and clean all ends of both battery cables. Use a wire brush or sandpaper. Clean the eyelet and the bolt to ensure you have a good connection.

You can try running that thick wire from the - battery post to where the black - cable connects to the frame. See if your voltage looks better.

Have you had issues with a dead batter?

 

Hi PAHonda,

Sorry about the vagueness. From what I recall there were three wires, WHT/BLUE was the one for the warning light, which was not working properly as per the manual. The other two, WHT/GREEN and BLK/YELLOW, both showed full battery voltage with the key on.

If I have high voltage with battery disconnected and lower voltage with battery connected, it would seem strange that the connection to the battery was poor? I would imagine that there would be no change or a small change if the connection was poor. Let me know if this analysis is completely backward.

I will try the extra ground cable tomorrow to see if that makes a difference.

Thanks!

 

I tried attaching a second battery ground cable as well, no difference. I am leaning toward trying a third alternator unless you guys can imagine any other strange reason this would happen!

Thanks for reading.