Electrical issue

[train2]

Hi, I have a 48 ford f1 6cyl 226h 6volt positive ground.Last week a headlight fuse blew,changed it and now I have no headlights,brake lites any lites at all.My horn works,gauges work but no lites in gauges,all fuses are good.Anyone know why this happened and how to fix it,could use some wiring diagraham s if you can send along,thanks in advance

[flatheadmurre]

http://www.vanpeltsales.com/FH_web/F...48-49truck.jpg

[51 MERC-CT]

Originally Posted by train2

Hi, I have a 48 ford f1 6cyl 226h 6volt positive ground.Last week a headlight fuse blew,changed it and now I have no headlights,brake lites any lites at all.My horn works,gauges work but no lites in gauges,all fuses are good.Anyone know why this happened and how to fix it,could use some wiring diagraham s if you can send along,thanks in advance

You say fuse(s) As I recall there is just one fuse for the lesser lights (brake,parking,dome etc.) and a Circuit breaker for the headlights. The circuit breaker should look like a small metal box. You could run a jumper across the box to check for continuity to see if it defective.

[flatheadmurre]

Or just measure over the circuit breaker with the load on if you get a reading with a dmm its faulthy or overloaded.
Dont hardwire a faulthy fuse for a long period or something else will melt on you.

[JSeery]

There is not a fuse shown on the wiring diagrams, there should be two circuit breakers. All of the lighting issues you are having are on the same circuit. Power from the battery (via the starter solenoid) goes through the ammeter to a connector between the two circuit breakers. One CB is connected to the lighting switch. The other CB is connected to the dome light switch, the lighting switch & the stop light switch.

If your truck has a fuse in place of the CB it may have been modified. Either way, you need to start with a voltmeter or a circuit tester (a light with two probes that will light up when voltage is present). Start by testing the input point from the battery to the CBs/fuses. You should have voltage there as I assume the truck is still running. Next test the output of each CB/fuse. One or both should not have any power as this is the only place all of the circuits you are having issues with come together.

Note: Just looked at the 46-47 truck wiring diagram and it as well does not have a fuse, but two circuit breakers. It appears your truck has been modified by removing the CB and installing a fuse panel. This should not be a big issue, the CB was mainly a nice item to attempt to not have a total blackout situation. A fuse will protest the wiring as well as a CB.

[BOSSY]

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Change the dimmer switch that feeds your headlight switch with juice.

[JSeery]

Originally Posted by BOSSY

Change the dimmer switch that feeds your headlight switch with juice.

Are you saying that you believe that the dimmer switch is the source of the dash lights and brake light problems?

[deuce_roadster]

I would find out what caused the original fuse to fail as the first thing. There must be a short somewhere.

[Drbrown]

Didn't say whether you are using the older glass-tube type fuses (they may look okay but be faulty) or the newer blade-type fuse (somewhat more reliable).

In the quest to follow your wiring around this might help ..... Your original Circuit Breaker Panel had two internal circuit breaker components "A" and "H" inside. They had coils on their contacts intended to heat-up to break the contact points open if there was excess amperage flowing thru them. In the perfect world once the coils cool-down the contacts reconnect and your lights come back on. However the coils/contacts can freeze in the "open" position (no lights) or (not applicable here) worse yet fuse together and your car burns up.

Per previous posts, sounds like someone removed/abandoned the original circuit breaker and substituted one or more modern fuses. You'll have to explore and test your wiring system.

I can't believe all the following would have been served by a single fuse: Beyond the original Circuit Breaker, the wiring for both the "A" and "H" circuit breaker components proceeded to the Dash Light Switch. From the Dash Light Switch, Circuit "A" proceeded to the gauge, tail/trunk/license and front Parking lights. From the Dash Light Switch, Circuit "H" proceeded to the Foot Floor (dimmer) Switch then onto the headlights and high beam dash indicator. Also tapping off the Circuit Breaker "A" terminal were the stop and pillar lights.

The horn and dash gauges were not fed thru the original circuit beaker unit but connected to its "feed" side.

[JSeery]

Just added some photos of 1947 circuit breaker connections under the dash if it help any.