Only ONE brake light now working, im stumped! Please HELP!

[trini-laser]

Hello all, I have been working on my explorer to get it past inspection, and one stubborn brake light will NOT work!

Ive replaced/done:

The bulb with brand new one
The brake light switch
Checked all fuses

Some things i've noticed that might help:

1. The taillight on that side works

2. The turn signal on that side works

3. Emergency lights work


Any help would be greatly appreciated!

 

[koda2000]

does your truck have (or has it ever had) wiring for a trailer? if so it's the first place i'd look.

did you check the bulb socket for power and any corrosion?

on your truck is the emergency flasher bulb the same as the brake light bulb? (i know it's not on my '00 and '01 so the fact that it works means nothing). the fact that the tail light works means nothing either.

other possibilities include broken wire somewhere or a bad multi-function switch.

 

[trini-laser]

does your truck have (or has it ever had) wiring for a trailer? if so it's the first place i'd look.

did you check the bulb socket for power and any corrosion?

on your truck is the emergency flasher bulb the same as the brake light bulb? (i know it's not on my '00 and '01 so the fact that it works means nothing). the fact that the tail light works means nothing either.

other possibilities include broken wire somewhere or a bad multi-function switch.

Thanks for your reply, the truck does not have any trailer wiring. I don't think the bulb socket is bad because the taillight will work on that side. When you say multi-function switch, is that the same as the turn signal switch?

 

[swshawaii]

If you have a tilting column, try tilt it down then all the way UP.
If that corrects the issue, it may be the MFS connection at fault.

http://www.explorerforum.com/forums/showthread.php?t=329048&highlight=tilt+steering+mfs

 

[koda2000]

Thanks for your reply, the truck does not have any trailer wiring. I don't think the bulb socket is bad because the taillight will work on that side. When you say multi-function switch, is that the same as the turn signal switch?

yes, but i would verify that the wiring isn't the problem first. it's cheaper (a 2 cent butt connector and a little shink rap) than a multi-function switch. figure out the color of the wire you're looking for and trace it back toward the dash. the wiring harness runs behind the driver's side kick panel, under the carpet on the driver's side. to get at it pop off the plastic trim that holds the carpet down. if necessary, purchase a cheap test light, connect it to a good ground an probe the wire for power.

tip: always test your test light on the cars battery first.

 

[trini-laser]

Thanks! I'm going to go perform those tests now

 

[deweyville65]

On my 96, the brake and tail lamp are the same bulb. The turn signal is separate. So, take your test light and probe the contacts while someone holds the brake pedal down, both should light. If only one contact has power, and the taillight works, you have a break in the brake light wire. Wires can break internally and not show on the outside of the wire. So begin probing the wire every few inches until you find where the break is. Hint, use a safety or straight pin to pierce the wire. A lot easier than using the probe on the tes tlight.

 

[Exploder919]

Strangely enough, I have a very similar problem in my 98 EX, one that I have yet to figure out. One day I even grabbed a voltage tester and got signal as expected, however, even with a new bulb, the problem still exists....

 

[trini-laser]

Thanks again for your help.

Well, I tried to tilt the steering column up and down to no avail. Still getting nothing from that side brake light.

I did notice though, that I have to move the multi-function switch to the right (which activates the turn signal) to get my wipers to come on and function properly through all the settings.

I did look at the wiring, it is all intact, nothing being grounded.

Would you say based on this information that the culprit is the multi-function switch??

 

[trini-laser]

On my 96, the brake and tail lamp are the same bulb. The turn signal is separate. So, take your test light and probe the contacts while someone holds the brake pedal down, both should light. If only one contact has power, and the taillight works, you have a break in the brake light wire. Wires can break internally and not show on the outside of the wire. So begin probing the wire every few inches until you find where the break is. Hint, use a safety or straight pin to pierce the wire. A lot easier than using the probe on the tes tlight.

Thanks for the suggestion, I am going to go try that right now.

 

[96eb96]

Hi!
In this thread I posted a diagram of the brake light system:
http://www.explorerforum.com/forums/showthread.php?t=375571
These are inexpensively available on Ebay as a Ford Service CD/DVD.

I do not see this circuit passing thru the Multi-Function switch!

A failure point could be the LOM in the center console if you have the message center, but you would lose BOTH lamps.

The failure has to be after the splice that divides the wiring for the bulbs. That splice is located :
585 mm from main branch for T/O to LH rear speaker

The guys who suggested the socket are probably on the right track!

If all else fails swap the sockets and see if the problem follows. When my socket failed there was no evidence of any damage in the socket. It even tested well with the meter, because inserting the bulb all the way in caused the terminal to separate. The sockets are cheap, replace both, keep the spare and they will outlast the truck.

 

[trini-laser]

Hi!
In this thread I posted a diagram of the brake light system:
http://www.explorerforum.com/forums/showthread.php?t=375571
These are inexpensively available on Ebay as a Ford Service CD/DVD.

I do not see this circuit passing thru the Multi-Function switch!

A failure point could be the LOM in the center console if you have the message center, but you would lose BOTH lamps.

The failure has to be after the splice that divides the wiring for the bulbs. That splice is located :
585 mm from main branch for T/O to LH rear speaker

The guys who suggested the socket are probably on the right track!

If all else fails swap the sockets and see if the problem follows. When my socket failed there was no evidence of any damage in the socket. It even tested well with the meter, because inserting the bulb all the way in caused the terminal to separate. The sockets are cheap, replace both, keep the spare and they will outlast the truck.

Thanks for your suggestions! I will swap the socket first and if that doesn't work, check out that splice. I will report back when done, so hopefully it may help others having the same issue.