I HAVE A 2001 F150 SUPER CREW, THE DASH LIGHT FUSE KEEPS BLOWING #18 ANY HELP. I AM IN THE DARK. THANKS:

 

I know this was a major issue in the superduty, but take the steering column apart and trace the wire that comes from the OD switch at the end of the lever... it goes across the steering column and wears thin and shorts out.... I have fixed one to two like this...

 

Have you done any modifications to the truck ( added a gauge, aftermarket radio, radar detector to the overhead console. etc ).

This is the fuse from main headlamp switch, going to the dimmer for the courtesy lamps as well as the dash lamps ( any lamp that the dimmer would operate ).

When you install a new fuse in the CJB ( aka Central Junction Box, cab fuse panel ) does it blow immediately after turning on your parking lamps, so does it take some time ?

If you rotate the dimmer all the way down, does the fuse still blow ?

 

No I have not done any aftermarket stuff, its all stock. It does not blow immediately, it take a day or two. I will try and turn dimmer down to see what it does. The CJB is the fuse panel inside by the hood release lever right? On the drivers side lower left?

 

If that does not sure it, we will need to slowly remove items to see when it stops to find the short. This will be time consuming.

Yes, that is the one.

 

Thanks I will get back after the weekend.

 

do this FIRST!!!!!

put new fuse in, turn ignition on, violently rip the the shifter down to 1 than P than 1 than P.... do this a few times, violently!!! if th efuse pops, you know the OD button harness is wearing thin and shorting to the column

This is how i diagnosed the issue.... if this is your problem... what your doing is stretching that wire harness from the OD button to over the steering column, shorting it out if the wire insulation is damaged...

 

Superduty is not the same as the F-150. Fuses are different, F18 is instrumentation circuit, not OD.

The OD control switch is power on the Hot in start or run position by CJB fuse # 29, and the other side is the PCM providing the ground.

The PCM providing ground is how the Electronic control knows when to flash the OD light if a sensor or actuator has an issue.

 

I
have had a new fuse in for 2 days with dash lights on low, so far so good. I will keep you posted.

 

Fuse blew again last night, it only lasted for about 40 minutes total over the 2 day period. Any other suggestions. In the dark. Thanks

 

At this point, the only thing I can think of that is easy, is to unplug it from the dimmer switch, and see if it blows still. This will remove a good part of the wiring.

 

Ok i give it a try.

 

Ok sscully, fuse has lasted 3 days now with the dimmer switch disconnected. Do you think all i need is a new switch? Any thoughts? Thanks.

 

That could be the cause, or it could be :
1. Radio
2. Function Selector
3. 4WD mode switch ( if 4x4 )
4. Ashtray illumination
5. steering column illumination
6. Circuit to / or instrument cluster illumination
7. Any of the power window / power door lock switches or the wiring for this to the doors
8. overhead console
9. adjustable pedal switch or rear sliding window switches ( if equiped ).

You can leave the dimmer switch connector C 245 unplugged ( 6 pin connector, all in 1 row ) and jumper the power in to the power out, and see if you blow a fuse.

Think the connector is 1/8" spade terminals. Should be able to make a jumper, and place it in the connector that is unplugged, by passing the dimmer switch all together.

The connector orientation should be with the tab to the right, pin #1 is on the top, Pin #6 is on the bottom.

Jumper pin #1 to pin #6 ( this should be Dark Blue w/ White stripe wire to light blue w/ red stripe wire ).

The panel illumination should be at full brightness ( just before the detent for the interior lamps ). I have not tried this myself, but the test for that section of the panel illumination is to test the switch with an ohm meter from pin #1 to pin #6, and as the dial is rotated from high to low ( brightness ) the resistance should go from low to high.
If the Resistance is removed, there is not a voltage drop in the circuit, lamps should be full bright.

This should be an easy test, next step is removing illumination via connectors ( need to remove the pin from the connector with the molex tool ) to see which branch is causing the problem if the fuse still blows.

 

I have a 2003 Supercab with the same problem. I tried a new switch with no luck. The switch is like $160.00. I would see if you know someone that has the same switch and try that before buying one. It is a special order. Most dealers don't have it in stock.