No dash lights, no tail lights....

[MikeD.]

2006 Sport 4x4 4.0. Driving home and all the dash lights including radio illumination, climate control lights, went out. All gages work fine just no illumination. Then discovered no tail-lights or fog lights. Brake lights, turn signals, head-lights work fine. Spent the day testing switches. Discovered no power at fuse #1, 5amp (instrument panel illumination). Relay tested good, all other fuses test good. Even the #1 fuse is good but no power to it. I ended up removing the fuse box and noticed this burned part on the back but I can't figure out what it is. Any help would be appreciated. Also any place to buy a new fuse box besides ebay. Thank you for your time.

 

[franklin2]

Where do you live? Here's one in Va on www.car-part.com. That looks like what Ford calls a "Smart Junction Box". I don't know if it needs to be programmed when you swap it in or not to make it compatible with the rest of the system. It is a computer just like the cluster, the engine/trans ECM. the ABS system, etc. They all talk to each other on a network in the truck.

Usually what they do is have the controls on the dash and the steering column hooked into the cluster. When you move a switch to command the lights to come on, the cluster computer recognizes what you want, and then sends a message over the network to the smart junction box which receives this command and then switches the relay which is burnt in your picture.

2006 Cabin Fuse Box Ford Ranger

3.0L AC AUTO RWD UDNDER DASH , PLAIN JANE

A​

YB023

$50​

Fleetwood Motors Company VARA USA-VA(King-William) Request_Quote 1-800-800-6826 Request_Insurance_Quote

 

[RonD]

Yes, its called the SJB(smart junction box) its the body computer

The Park light relay is on that board

When you turn on the park lights that relay should close and send 12v out to dash lights(dimmer) and front and rear tail lights
Front tail lights use a different wire on a different connector on the SJB than the rear
So if the front park lights work then relay should be OK

Yes, there is not alot of repair you can do to an SJB, wrecking yard is best bet, or you can go to a Ford Dealer

 

[MikeD.]

Where do you live? Here's one in Va on www.car-part.com. That looks like what Ford calls a "Smart Junction Box". I don't know if it needs to be programmed when you swap it in or not to make it compatible with the rest of the system. It is a computer just like the cluster, the engine/trans ECM. the ABS system, etc. They all talk to each other on a network in the truck.

Usually what they do is have the controls on the dash and the steering column hooked into the cluster. When you move a switch to command the lights to come on, the cluster computer recognizes what you want, and then sends a message over the network to the smart junction box which receives this command and then switches the relay which is burnt in your picture.

2006 Cabin Fuse Box Ford Ranger

3.0L AC AUTO RWD UDNDER DASH , PLAIN JANE

A​

YB023

$50​

Fleetwood Motors Company VARA USA-VA(King-William) Request_Quote 1-800-800-6826 Request_Insurance_Quote

Thanks, I will check that page out. Mine is 4.0 automatic. I'm in Oklahoma

 

[MikeD.]

Yes, its called the SJB(smart junction box) its the body computer

The Park light relay is on that board

When you turn on the park lights that relay should close and send 12v out to dash lights(dimmer) and front and rear tail lights
Front tail lights use a different wire on a different connector on the SJB than the rear
So if the front park lights work then relay should be OK

Yes, there is not alot of repair you can do to an SJB, wrecking yard is best bet, or you can go to a Ford Dealer

Thanks, I did test the relay and it's getting 12v. No park lights front or rear.

 

[RonD]

Yes, the park light relay get 12volts all the time, not a key on/off circuit

The head light switch GROUNDS the relay to activate it, diagram below

The black/pink wire in the diagram goes to the rear tail lights

So 3 different connectors on the SJB are used for dash, front and rear lights, but if none are working then either the head light switch is not grounding the relay(white/black wire) or relay is bad
From the looks of the board I am guessing relay is bad, unless you hear it "click" with headlight switch on

 

[MikeD.]

Update: Found a SJB with EXACT part number from Spalding Auto Parts in WA. Installed yesterday. Now all exterior lights are working. Only lights not working are dash and climate control/radio illumination. Going to test dimmer per Mitchell's pin 2 and 4 test. I have opened the dimmer everything LOOKS good. Clean no corrosion. What can go bad in a dimmer switch?

 

[RonD]

Good stuff

Dimmer only gets 12v with park or headlights on, just saying

Dimmer has a separate switch inside, does that work to turn on the dome light?

So with park light switch on do you get 12v at the dimmer?
Fuse 1 in SJB should have 12v Park lights on, that fuse sends the 12v to the dimmer for dash lights

 

[MikeD.]

Just to wrap things up.....went to local LKQ (pull-a-part) they had 5 rangers so I picked around and found the best dimmer switch, $6+tax. Installed it, everything working great. Moved truck to clean up garage. Came back later to move truck.........no power locks lol.....Would not communicate with new fuse box (SJB). Back to Mitchells to find out how to program key fob. Easy, less than 30 seconds. Now, everything is working. On to the next project.....

 

[thcscubajohn]

I had a similar issue, it was my headlight switch. It went bad and caused me to loose all dash lights and tail lights and it would only act up in certain positions. I also had issues with my tail light harness.