Dash light

[dngalura]

Learned Gentlemen of the Pagoda,
Please help on this one.
A week ago, while enjoying a ride on my '70 280sl, suddenlly the dash light for the alternator came on, which never happened before. Incresing the rpm, it will make it dim just a little bit. I've been reading the forum on the subject of alternator/voltage regulator. I was so sure that it must be one of these or both. I went ahead and replaced both with new Bosch parts (alternator & vr). Today, I drove it around and the light still stays on. Went to AutoZone and had the charging system checked and the guy said its not charging and these are new parts. I didn't alter anything, the wiring the same.
Otherwise, the car runs well and the battery is fully charged.
Will appreciate your imput. Thanks.

Dan '70 280sl

[BHap]

Did they check for charging at the battery or directly from the alternator?  maybe bad battery cables...  i would start chasing wires to be sure you have good connections

Bob Happe
Pittsburgh, Pa
1970 280SL, white/black 4 speed

[dngalura]

Bob,
Thanks.
They just checked the battery, not directly at the alternator. The battery cables have never been replaced, could it be these? What do I look for on the cables, or just go ahead and replce them?
What else to look for?


Dan

[Bob G ✝︎]

Check the ground connect this is were the positive cable is attached to a ground by the starter, Also check your brake fluid resivors the light was also designed to warn the driver of low brake fluid levels.

Bob Geco

[dngalura]

Bobg,
Now that you mentioned re: low break fluid would light up the dash light as well. I recently had my front breaks and hoses replaced, the car breaks ok. Now looking at the break fluid compensating chamber, it's hard to see really the level of fluid especially the front one, because of discoloration. I opened the closing cover, I can see break fluid, but is this a sure sign that both chambers has enough fluid? Can I open the chambers after removing the plugs? Or is there another way of checking. I don't want to break anything.
By the way, checking the wires, don't see any loose ones. I have not check the starter connections yet.
Thanks.

Dan

[dngalura]

Bobg,
Sorry about the spelling of Brake, confused! ignore "breaks".

Dan

[dngalura]

Hi Folks,
I finally solved the red light on my dash, after a lot of reading and following the thread and trouble shooting (and along the way learned a lot about the pagoda), it's the alternator, and with the new one, it solved all my concern.
Thank you all. Until next time. ( Right now I'm listening very careful
to a rattle sound coming from the right rear wheel, could be axle(?))..


Dan

[jeffc280sl]

Glad you fixed the light issue.  With regards to the rattle in the right wheel the sound could be from many things.  Check the splash plate to see if it is bent and coming in contact with the rotor. Next I would check brake pads.  Folowing that I would remove the wheel, caliper and rotor and inspect the emergency brake shoes, springs, etc.  I've just rebuilt an axle and recommend you try and  get to the bottom of the noise.  It is a pretty easy subsystem to maintain.  A special wrench is needed to remove the bearing if needed.  I suggest you look at Joe Alexander's excellent write up on the rear wheel bearing tour prior to doing this job.

Jeff C.
1970 280SL 4-speed