Matt300ZXT
New Member
I posted this over on Club Lexus, but figured some people here might not read that forum and might be able to help, here's my original post: (more posted below my original thread)
Ok so I'm cursed with the all too familiar battery warning light on the dash flickering on and off; and as of late, coming on and staying on way longer and way more often. I have replaced the p/s pump and alternator with low mileage used units. This is a 93 SC400 by the way.
The p/s pump was so clean I could eat off of it and the new alternator was clean too. I had it tested before installing it and Auto Zone passed it. I installed the pieces and got the car running, and drove perfect for about 3 days, then the light came back on. I drove it for a few more days with it barely coming on at all, and then it got to where it started coming on more and more and staying on longer.
Fast forward to last night, I tore the alternator off again (it is possible to remove it from the top with the p/s pump and pulley, and fan shroud all still in place) and took it to O'reilly to have it tested. It passed all 3 of the tests 3 seperate times. I did notice a little gunk on the 3 prongs on the plug so I scraped them real good, and then cleaned the prongs on the electrical connector on the car as best I could from under the car at 8 at night. I plugged it back in and heard the click noise (like when putting plug wires on a spark plug) and then tightened the main wire down real tight. Got the whole car buttoned back up and went to go to work this morning, and in the roughly 2 miles I drove it before parking it and taking another car, the light stayed on almost the whole time. However, no headlight flickering or loss of power or anything like that.
So here's what I've done so far:
Replaced p/s pump with new no leak unit
Replaced alternator with clean working unit that passed 5 3-part tests
Cleaned connectors on the back of the alternator
Cleaned electrical connector on the car
Checked the 150a alternator fuse and 60a main fuse, none look blown
I'm probably going to replace the alternator fuse anyway. I know people say clean connections and check grounds, if someone could tell me what connections to clean and what grounds to check and clean I'll be more than happy to do it. I'm used to old Datsun Z cars where I could easily see where the grounds go to and where wires connect as everything is in plain sight on those and everythings easy to get to, not so much on this Lexus. This is really baffling me.
Ok I also added in a reply over there that I put a volt meter on the battery terminals while the car was running this afternoon. It shows 13.3 volts with or without the radio and heat on. Had to try and put a little load on it. Stays the same at 1500RPM and 2000RPM, so no flucuation there. The battery at rest with the car shut off is 11.5 volts. However the alternator does have a kind of supercharger like sound to it, but tested fine at 2 different auto parts stores, so I don't know.
Ok so I'm cursed with the all too familiar battery warning light on the dash flickering on and off; and as of late, coming on and staying on way longer and way more often. I have replaced the p/s pump and alternator with low mileage used units. This is a 93 SC400 by the way.
The p/s pump was so clean I could eat off of it and the new alternator was clean too. I had it tested before installing it and Auto Zone passed it. I installed the pieces and got the car running, and drove perfect for about 3 days, then the light came back on. I drove it for a few more days with it barely coming on at all, and then it got to where it started coming on more and more and staying on longer.
Fast forward to last night, I tore the alternator off again (it is possible to remove it from the top with the p/s pump and pulley, and fan shroud all still in place) and took it to O'reilly to have it tested. It passed all 3 of the tests 3 seperate times. I did notice a little gunk on the 3 prongs on the plug so I scraped them real good, and then cleaned the prongs on the electrical connector on the car as best I could from under the car at 8 at night. I plugged it back in and heard the click noise (like when putting plug wires on a spark plug) and then tightened the main wire down real tight. Got the whole car buttoned back up and went to go to work this morning, and in the roughly 2 miles I drove it before parking it and taking another car, the light stayed on almost the whole time. However, no headlight flickering or loss of power or anything like that.
So here's what I've done so far:
Replaced p/s pump with new no leak unit
Replaced alternator with clean working unit that passed 5 3-part tests
Cleaned connectors on the back of the alternator
Cleaned electrical connector on the car
Checked the 150a alternator fuse and 60a main fuse, none look blown
I'm probably going to replace the alternator fuse anyway. I know people say clean connections and check grounds, if someone could tell me what connections to clean and what grounds to check and clean I'll be more than happy to do it. I'm used to old Datsun Z cars where I could easily see where the grounds go to and where wires connect as everything is in plain sight on those and everythings easy to get to, not so much on this Lexus. This is really baffling me.
Ok I also added in a reply over there that I put a volt meter on the battery terminals while the car was running this afternoon. It shows 13.3 volts with or without the radio and heat on. Had to try and put a little load on it. Stays the same at 1500RPM and 2000RPM, so no flucuation there. The battery at rest with the car shut off is 11.5 volts. However the alternator does have a kind of supercharger like sound to it, but tested fine at 2 different auto parts stores, so I don't know.
