Hi! I own a 1984 mazda rx7 GSL 1.1L and I'm having an issue with my dome light... it also affects a few other things like buzzer and chimes. When I went to replace the bulb I inadvertently touched metal because the bulb blew and left burn marks on either side of the bulb. Checked fuses and I can't seem to locate any that are blown? Tried replacing it with another but no go. Is anyone here familiar with this kind of situation?

Thanks in advance for any help,
David

Bulb replaced/nothing!

Burn marks where the bulb shorted

Another angle

 

are you getting electricity to anything else inside the car?

 

Hi, yes..: power to cig lighter. Car starts and runs fine. No chimes and clock. Orig radio lights up when button pressed but no sound. Changed out 10a fuses even though they look good but no luck.

I thought originally that a simple fuse might be the problem?

any ideas? Thanks

 

anybody???

 

Have you tested the switch? You should be able to use an ohm meter and document what readings you get when operating the switch depowered. Also, do the start cylinder, cig ring, and door light on the exterior work?

Area 50H page 5:30 https://www.foxed.ca/rx7manual/manua...g_Diagrams.pdf

 

Hi, the rear view mirror is removed from the car. Cig lighter works but no chimes, radio or clock. I’m not really equipped to test the switch. Even removed does that switch matter?

David

 

The Cig liter and ignition cylinder have a circle that lights up when the lights are turned on. The drivers door has a light also when you open the door. Don't worry about the door light as much because they don't work most of the time. The cig and ignition should light up though. The cig and ignition lights are controller by that mirror switch by completing the circuit I linked to. To help, I'd need some values though. I'll try and make a write up by pulling mine off my car and showing you want and how to test.

The mirror switch can be tested off the car with a $7 Harbor Fright multimeter. If your more comfortable with wiring, Amazon has some cheap multimeter that do a lot more for under $15. Really depends on how much you you'd use it.

https://www.harborfreight.com/7-func...gaAnCWEALw_wcB

I like this one on Amazon because it will check if AC power is on using Non-Contact induction plus all the car DC stuff.

 

Ok, does the switch complete the circuit? I did connect the dome light again but still nothing. Cig lighter still getting power. Why would the clock, chimes and radio (lights up but no sound) still not work. Maybe the dome switch. I’d love to see how you would approach this.

wouldnt a fuse blow?

 

The cig lighter, clock, and chimes have nothing to do with the overhead light switch or it's operation. The overhead light switch only controls the overhead light, cig light, door handle light, and ignition switch light. Sounds like there are multiple problems.

The door switch would control the chimes and door handle light. It could be that that there is a common ground that is effecting everything you mention.

 

You don’t think they are on the same circuit? Why do you think any fuses weren’t blown?

 

Could you explain “common ground?”

thanks… still learning 😎

 

Your lighting is wired different then the light on my 1984 base model. The light prong on yours has a black wire. Mine has does not have a wire on the drivers side. If you look at the back, mine has a Blue/Yellow (LY) and that supplies 12V to the overhead light. That same Blue Yellow has a T before going to the overhead light that supplies 12V to the clock. This 12V circuit is fused by a 15A fused at X-03 in the schematic which is the main fuse block.

Can you take a pic of the back of your with the drivers side on the left of the pic?

(Drivers side is the left side in this photo)

(Drivers side is the left side in this photo)


I've marked all the things that are controlled by this 15A fuse in blue.

 

A fuse could be blown but I thought you checked them.

 

Mine is exactly like yours on the backside. Maybe my black wire on the front is ground?

 

Also, your fuse is a 15a? Mine is a 10a.

 

Here is the comment ground behind the center radio area.

This is the backside. It's kind of hard to stick your head in the passenger footwell.



This is the front side. The ground is attached to the stud head in the lower righr.

 

Do you know how to test the two wires that the dome light attaches to? When I removed the dome light on mine… the two wires on the back connect to the two wires for power?

Thanks so much

 

On the car side harness, the Blue/Yellow is 12VDC. With the black probe on the volt meter on a good metal ground (the screw hole for the overhead light will work), put the red probe on the volt meter on the Blue/Yellow harness side bullet connector. It should read 12VDC or something close. If you do not have 12VDC, then neither the fuse is blown or you have cut/open inn that wire.

 

Ok, that makes sense..: do you test with the battery off? Also, do you know if there might be a relay that is part of that system?

 

Also, what would I set my meter to for testing 12v?

 

Ignition turned on to test or not?

 

1. To measure voltage, the battery must be connected.
2. There is no relay.
3. Set the meter to the DC setting.
4. So the ignition to the ON position (just before starting) OR you can start if you want. To test to ensure you have the ignition in the ON position, You should be able to turn the headlight on and they should be light.

 

I will try and check at some point. At the moment experiencing a little health issue. I am very grateful for all your help!

Thank you

 

Here is how to test the light assembly removed from the car. Take a 12V source, wire to battery or a 12V standalone power supply, and connect to the Blue/Yellow male bullet connector.

1. Take the ground and connect it the the female bullet connecter. Move the On-Door-Off switch to the Door position. Light should light.
2. Move the ground to the super small ground screw with the two black wires. Move the On-Door-Off switch to the On position. Light should light.
3. Flip the map light to both the right and left. Map light should light.

This test will confirm the dome light assembly itself is working.