courtesy lights no power

[Dkennel]

Gave the car a good cleaning today, just as I am almost finished I start messing with the courtesy lights, get always confused with the settings. I work on the drivers side light, all of a sudden no more light regardless of switch setting, no constant, no door switch, I wiggle the door switch, no fix, check the passenger courtesy light, no power either??? check my fuse block, #4 is o.k. and my clock works, I pull the driver door light, wiggle contacts, no luck, seems both lights get no power, but my fuse is ok, I am thinking poor contact somewhere. Any ideas? suggestions? anybody same problem in past? since it is both lights it should be central close to the fuse block?

[pete3799]

^^+1
Check for power on both sides of the fuse.

[Dkennel]

the circuit also supplies power to the clock, and my clock is just working fine, fuse looks fine, i'll check for power

[Dkennel]

yup got power on both sides of the fuse, there is constant power to that circuit, but lights do not work in any of the switch positions, and that's on both sides....

[Dkennel]

radio works, glove compartment light works, luggage light, and clock works, but both interior lights do not....how are the connection wires routed and where could the current be interrupted to both sides?

[Dkennel]

...and the lights should work on constant position...I am baffled by this, thought for sure I somehow had blown the fuse

[Dkennel]

just pulled the driver side interior light out, I have no power on either the constant power or the door switch cable...there is good power on the fuse block on both sides of the fuse..light worked fine this morning...I don't understand

[D911SC]

I'm not sure if this applies to an 87, but on my 83 the power and gnd are connected near the luggage compartment light. There are a couple of wires with simple spade type connectors there. These feed the courtesy lights. If these wires are not connected everything else will work but the courtesy lights.

I couldn't work it out from the above wiring diagram but the one in my Bentley pointed me to the luggage compartment light. You might find it easier to trace the switch wire from the door switch. Mine went from the door panel up through the bulk head and then connected to to the wires feeding the luggage light as mentioned.

[D911SC]

PS. If it's like an 83 make sure you are troubleshooting the light that has two wires coming into one end on the light fitting. This is the one that then feeds the other light (right hand side on my RHD car).

[Dkennel]

thanks d911sc, I couldn't find a wiring diagram in my Bentley manual that shows the courtesy/interior lights, I'll check the luggage light and the right side indoor light, I know I have power to the luggage light, hopefully I can find an answer there.

[Dkennel]

Porsche 911 Wiring Harnesses FRONT Luggage Compartment Interior Lights Sunroof Parts

found this for the wiring harness, does appear that the interior lights for the coupe plug in close to the luggage light...

[msterling]

Great info! I have the same problem with my 88 911 Cab. I rarely need those lights but they do not work. I'll be taking a look at this.

[Brorag]

Just finished rewiring that circuit.
I've got the 87 cab--the light is mounted over the windshield.
Try the easy stuff first.
Don't know if we're talking about the same light, or if you have the coupe and the light is different, but:
the light unit itself was switched with 3 positions; on/off/on with door open. The door switch provides a ground to the light in one of those positons.
Do you have that fixture? If so, it may be in the off positon.

[msterling]

Originally Posted by Brorag

Just finished rewiring that circuit.
I've got the 87 cab--the light is mounted over the windshield.
Try the easy stuff first.
Don't know if we're talking about the same light, or if you have the coupe and the light is different, but:
the light unit itself was switched with 3 positions; on/off/on with door open. The door switch provides a ground to the light in one of those positons.
Do you have that fixture? If so, it may be in the off positon.

Yup, I found that the whole light (above the mirror) swivels to actuate a 3-position switch. Mine was in the OFF position. Duh! Now that I know how to work it; it works!

[Dkennel]

87 coupe, similar light, but one over each door.
Here is my update, wiggled connectors close to the luggage light and I have power back to the door lights, but so far only in the constant on position, still no light in the door position, not on either side and not with either door switch, doubt it is the door switches, will need to research the connectors under the hood more, does anybody know which connectors go to the interior lights? I'll take pictures next time I get under there.

[Porboynz]

On a 1972 (maybe the same, why change?) the same fused power feed operates the interior lights for the manual on/off at the light fitting and the door operated position. When using the manual "on'' position the path to earth for the bulb is through the light fittings spring mounting clip to the bodywork. Sometimes a fold of hood cloth can get in the way or surface corrosion needs cleaning. When in the door switch operated position then the door pillar switches are the path to earth. So to test you can pop the rubber off and unscrew a switch. You should be able to measure the 12v on the wire. Maybe when you were messing with the light fittings you swapped the wires or dislodged the door switch wires?

[D911SC]

The door switch goes to the luggage compartment connections and then to the light. I would disconnect the connectors and clean with emery paper. You might find it works after doing this.

It might be worth cleaning the connections at the light itself. Maybe this is stopping the circuit being completed by the door switch.

If it's still not working you could troubleshoot by getting a spare wire and grounding at each connection to see where the issue is (ie. ground at the light while it's in the 'door open' position or ground at the luggage compartment connection, etc)

[proporsche]

Hello Dietmar
Try this.Your front trunk light is in the same el.system as is interior lights.Under the front hood switch (follow the wire) is power supply and grounds to these lights.There you need to find a connector which is only one way power with a resistor inside.It is about 10cm long try to find this and measure that connector if the power goes trough it .That could your interior lights problem.Also check ground connection there(under trunk switch behind the hood shock)
i hope this will help you
any Q. my mail is proporsche@yahoo.com

proporsche

[Dkennel]

Finally resolved this issue, as so often it was two separate issues. As previously stated I must have had a poor connection near the luggage light, after wiggling that connector lights came back on, at some point in my process of checking things passenger door switch activated lights again, but nothing on driver side....so I pulled the door switch on driver side to find that the ground wire had broke off. Managed to fish the wire through the switch hole and re-soldered the ground wire. All works fine now as intended! Case closed, thanks everybody.

[Rick W]

I know this is an old thread but this is the exact same scenario I am having with my interior lights. Does anyone know the exact location of the interior light wire connection near the trunk light, or have a picture of the connection?