Tail and dash lights still don't work after new relay and fuses.

B

BrockWalls

Member
:
Focus SE 1L
Basically what the title says. My P5 is becoming kind of a pain, because neither of these things work, which means I can't drive at night.

I've already changed the relay under the hood. All of the fuses were good, as were the fuses under the dash. Taped off a couple of exposed wires, but still nothing. Honestly it's kind of turning me off Mazda (that, and the rust. Ugh.)

TL;DR Tail lights don't work, at wits end.
 
You did the TNS relay right ??

TNSrelay_zpsc77c003b.jpg
 
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It could be your switch itself... Bad stock ??

Maybe check wiring in the steering column ??

See if the switch is "switching".
 
Replaced the switch, too. Bought a few at a junkyard, but no dice. I don't think it'd be in the steering column since the head lights and fog lights still work. If I have time, I think I'll take a look regardless.
 
I'm trying to make sense of the wiring diagrams,... It looks like your TNS relay is working if your fogs work.

Try pulling the tail fuse and test for +12V at the fuse connector. It looks like it should be switching on and off with the switch on the stock (headlight switch).

There should be +12V between ground and one of the connector pins when the running lights are switched on.

Try to test for +12 V on the light green/black wire on the FB-06 connector.

You've probably got a broken/bad connection somewhere as opposed a short or you'd blow a fuse.



If it were me, and there was no voltage getting to the fuse, I'd try feeding +12V directly to the LG/B wire to see if the running lights kick in.


tnsrelay1_zpsdc379521.jpg



tnsrelay2_zps691dae8b.jpg
 
Dude,.. Do this.

My car was off and I attached one end of that little wire directly to the battery.
I forgot about the little test points on top of the fuses.

My running lights came on.


IMG_20141219_165133_zps83ffb949.jpg
 
If you are lucky enough to have your running lights come on using the wire, then you can put a wire on the fuse as shown.

Make sure the wire goes on the same terminal as shown so that the battery power is going through the fuse so the circuit is protected.

Just run a wire from the battery (doesn't have to be too thick) to a switch somewhere (there's an empty spot beside the fog lamp switch) then to that fuse.

You may want a second in-line fuse on that wire right at the battery.

(You can just install a jumper wire for the time being so you can drive at night,.. be aware that the wire wrapped around the fuse can kinda expand the connector it plugs into,.. I didn't plug the fuse in for this reason)


fusewire_zps18296a0c.jpg
 
You can use a spare fuse cut in half to make a proper fitting terminal connector.


PPLUG_zps6c776d16.jpg
 
BrockWalls said:
The thing is though is that the DRLs work. Would doing this still help?
Click to expand...

Yea, it's a separate circuit.

Only my running lights came on.

You can "Jerry Rig" it really easy if your running lights come on.

With the key out of your car touch a wire from the positive battery to the top of the fuse and see if they turn on. Real easy,.. takes two minutes,... I didn't blow anything up so you won't.
 
I had this same issue a few months ago (although no drl's, 'murica). i found that i had a short somewhere on the circuit, but couldn't pinpoint where, other than it was after it came into the vehicle from the engine bay. I ended up running a new wire from the firewall to the lights, and dash, and heater controls. Haven't had any issues since.
 
BrockWalls said:
Alright, I admit I'm a bit confused. By "running lights" you do mean tail lights, correct?
Click to expand...

Yes,... All the lights that come on when your light switch is in the first position.
Tail lights, four at the front of the car and your dash lights.

You most likely have a bad connection/broken wire somewhere that can be really hard to locate.

If this works for you, then you can bypass the bad circuit much like how Balls did.

I'm guessing the power isn't getting to the "tail light" circuit.

Go and do the wire trick to see if your taillights fire up. (You won't blow anything up,... but your "tail" circuit should turn on)
 
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I found this diagram too,...

Both the "headlight" and "tail" circuit are powered by the same "power feed" wire,... "P" in the diagram.

You may be able to feed +12v to the combination switch so you can use the headlight switch normally (much like how Balls did). It all depends where the bad connection is on your car.

Can you manage to get a voltage reading on that "P" terminal of your connector. You may be able to put a +12 wire straight to that "P" terminal.
(the DRL's may work independent of the combination switch,... there's a lot of electrical schematics missing from the P5 Wiring diagrams)

Combinationswitch_zps3f7630f6.jpg
 
To show you what I mean,..

When I did this,....

IMG_20141222_082734_zps6vtia2gu.jpg



IMG_20141222_082657_zpsfrjir4ey.jpg







This Happened,...


IMG_20141222_082614_zpshvsejset.jpg



IMG_20141222_082559_zpsip3b0vh9.jpg



IMG_20141222_082920_zpst002pksw.jpg




The door ajar dinger and dimmer switch were working normally.
 
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Great. I imagine that'll fix my problem, because none of those lights, nor the finger that rings when I've left my lights on work. Thanks for your help.

Weird that the simplest things fix the weirdest issues.
 
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Just a couple last questions: I see the blue wire going in to the connector. Does the connector plug back into anything?

And I have to have a switch or else the lights will just stay on and kill the battery, correct? If I have to, I think I'll tap it into the fog light switch, because my fogs basically point at the ground.
 
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