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Discussion Starter #1
The gear selection/indicator light has never worked on my 83 380sl so I ordered a few LED replacements and removed the console cover tonight to switch it out.

The problem is, upon removal the bulb doesn't appear to be burned out and none of the replacements work either. I tried three.

I left one of the LEDs installed and replaced everything. My fuses all look ok and everything else seems to work (hazard switch, windows and mirror adjuster).

Any ideas?
 

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Discussion Starter #2
Also, just a note, I am unable to check the socket as I don't have a meter but I'm going to buy one. I just hope I can get the probe in their correctly without shorting it against the wall of the socket. The socket is extremely small.
 

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Hi There:

I would try the tester and see if you have a short. BTW, I have to replace the bulb in my wife's gear indicator -- what is the OEM bulb size so I can pick one up from the parts store? I assume I will have to remove the ashtray and the shifter bezel to access the socket?

Thanks,

Ted
 

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Discussion Starter #4
Hi There:

I would try the tester and see if you have a short. BTW, I have to replace the bulb in my wife's gear indicator -- what is the OEM bulb size so I can pick one up from the parts store? I assume I will have to remove the ashtray and the shifter bezel to access the socket?

Thanks,

Ted
My wife's gear indicator is usually "Park" :grin

I purchased an LED replacement online but the parts store probably has a regular lamp. It's this one:

https://www.interlight.biz/light-bulb/PHILIPS-12829


Note: I just found that reseller via online search, I'm not familiar with them specifically.

It's a really tiny bulb.

To get the bulb, just remove the ashtray and remove the two screws holding the ash tray plate on. Then pull the plate out, and gently slide the wood console cover back and up. I had to put the transmission in a middle gear for clearance.

Instructions with pics are here:
Gear Selector Light Replacement

The bulb shown in those pics is not the same bulb as in my model (or yours).
 

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OEM bulb is a BA7S - the ground point is forward of the shifter mounts on the prop shaft tunnel and is often gummed up with years of crud causing an open circuit. Wire brush it clean and then give it a try.

LED bulbs are available with a BA7S base.
 

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Discussion Starter #7
OEM bulb is a BA7S - the ground point is forward of the shifter mounts on the prop shaft tunnel and is often gummed up with years of crud causing an open circuit. Wire brush it clean and then give it a try.

LED bulbs are available with a BA7S base.
Thanks I'll look for that.
 

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Discussion Starter #8
...the ground point is forward of the shifter mounts on the prop shaft tunnel and is often gummed up with years of crud causing an open circuit. Wire brush it clean and then give it a try.
Is this reachable if I only remove the wood surround from gear shift area of the console? Or do I need to remove the climate control surround as well?
 

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Do you have a multi meter?

Page 122 of the ETM for your car shows the wiring for the shift case. There are two wires leading to the socket for the BA7S bulb. The ground (brown wire) is tied to the ground for the cigar lighter and radio and terminates at body grounding point G102 which is behind your right speaker. You don't have to pull your glovebox and right speaker, just do a continuity check for ground at the shift case light socket (copper on the side of the socket - not at the base). If you can get your hands on a multi meter, I can talk you through this if you don't know how.

The power lead for your shift case light is a grey with purple hash wire that should have 12V (non dimmable) anytime your light switch is in head or parking lights.

I misled you based on the wiring of my shift case light from a 1973 car. The grounding method is different in my car.

Is your cigar lighter operative?
 

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Discussion Starter #10
Do you have a multi meter?

Page 122 of the ETM for your car shows the wiring for the shift case. There are two wires leading to the socket for the BA7S bulb. The ground (brown wire) is tied to the ground for the cigar lighter and radio and terminates at body grounding point G102 which is behind your right speaker. You don't have to pull your glovebox and right speaker, just do a continuity check for ground at the shift case light socket (copper on the side of the socket - not at the base). If you can get your hands on a multi meter, I can talk you through this if you don't know how.

The power lead for your shift case light is a grey with purple hash wire that should have 12V (non dimmable) anytime your light switch is in head or parking lights.

I misled you based on the wiring of my shift case light from a 1973 car. The grounding method is different in my car.

Is your cigar lighter operative?
The cigar lighter is also not operative. The previous owner installed an aftermarket radio and it is operational, though. I have no idea if he disrupted the wiring at all. From your description I was able to find the wiring diagram and also the component location map. I am really a complete novice when it comes to electrical work, I have to admit. However the fact that the radio seems to work would indicate that the grounding point may not be the issue? Unless the PO rewired the ground somehow?


I do not have a multimeter but I will buy one. I have a basic tester like this one:


I can use that to see if the socket has power and (if I can get the ground to touch the edge of the socket...it reall is tiny) if it is grounded but it won't tell me much else.

Greatly appreciate the help you have provided. I'm learning quite a bit already. Thanks!
 

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Aftermarket radio may have interrupted your ground at the cigar lighter and shift case light. A multi meter will help you determine continuity in that circuit.

I found an unused, random, incorrect 2 pole connector at my cigar lighter. I found the correct one the first time I went into the panels of the console. I still have no idea what optional equipment that other connector could have been for.
 

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Discussion Starter #12
Aftermarket radio may have interrupted your ground at the cigar lighter and shift case light. A multi meter will help you determine continuity in that circuit.

I found an unused, random, incorrect 2 pole connector at my cigar lighter. I found the correct one the first time I went into the panels of the console. I still have no idea what optional equipment that other connector could have been for.
Indeed it is as you described, the ground connection of that circuit has been disrupted. I was able to close the circuit on my tester by running a lead to a different ground point (I used the seat belt bolt next to the seat). There is power going to the socket, but no ground connection.

The radio does work, so that is grounded somehow...

I guess my next step is to pull the radio? Or do I need to remove the wood console cover from the climate control area? Or both?

Thanks for your help. Much appreciated!
 

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I looked at an '84 with radio, climate control etc. all removed. All that is left is the console with carpet sides. I could not see the grounding point.
 

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Discussion Starter #14
I think the grounding point is over near the fuse box.

My thought right now is that the PO cut the line when installing the aftermarket radio and found some other way to ground it.
 

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Wiring diagram states (partial) behind center of the instrument cluster
 

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ETM says G102 is to the right of the glovebox liner - there is a picture of it but I think our suspicion of a clipped brown wire behind the radio is what is keeping the cigar lighter and shift case light from operating.

You would have to pull the A/C panel and likely pull the radio to get enough space to find and fix that wire. Your cigar lighter is the second most high draw item in the car; I would want to know that the ground wire for that item is secure.

You may find other carnage in that area - I did when I replaced my console.
 

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Discussion Starter #17
Sorry to ask a basic question, but I've been reading through the EG and doing some forum searches and have yet to find instructions on removing the climate control panel. Since I have the ash tray frame removed, mine appears to be loose around the bottom edge -- not sure if this is the way it's supposed to be or not. My instinct is to pull on this edge slightly while also pulling down but I am fearful I will damage this panel. How is it supposed to be held on?

I may try to pull the radio first, seems less risky.
 

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I'm not positive which AC system you have - guessing ACII. Article 83-635 in the service manual covers removal of the panel and control unit. It's too big to attach here but it says:

1. Disconnect battery
2. Remove radio
3. Remove ash tray with holder (you already did that)
4. Carefully pull covering for controls at bottom out of holders

After that, there are screws at the top and sides of the control unit that enable you to pull and unplug. From there, you would probably have enough room to find the damage and fix it.

Maybe you will find it after pulling the radio.
 

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In '83 it would be ACCIII. Section may be the same in the manual. I'll check if I can find it.

EDIT: Yep. 83.9-635
 

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I just removed all the panels to refinish them. The CC panel will come out pretty easily once the ashtray mount comes out. There are two wooden tabs that keep it tucked under the radio. Just slowly jiggle it a bit and it will come out really easily.

The pushbutton control is attached by 2 phillips screws. I found it easier to disconnect the wires and lights first then removing the cc unit from the wood panel on the bench.

Once off, with a little goo gone, you can clean those buttons pretty well. Mine shined up great.

Once you have that panel out, you'll have access to all those wires with ease!

My ashtray hasn't worked in years but I'm redoing the entire interior, sO its time to finally sort it out. The first step is to test the connector with a multimeter. good luck!
 
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