I'm new on the forum and just acquired a 1972 Ford F350 Camper Special with a Mitchell and Sons Funmobile camper on the back. I am having a problem with my ignition. The yellow wire on the plug that goes to the key has no power. I ran a jumper wire from the batter 12.8volts to this yellow wire and it then in turn makes the truck operate like normal(with the exception of mission dash lights). Without running the jumper wire I have no power at the key and the only thing that works is the horn.
Has anyone had this problem before? I have been through the forum as thoroughly as I could without wasting too much time, as I have already spent several hours tracing wires with no luck.
Also, my brake warning light is on solid with the key on. I am not sure if this is related or not yet. As I have not read into the brake warning system.
51JohnDeereB » Mon May 02, 2016 10:48 pm
Hi all,
I'm new on the forum and just acquired a 1972 Ford F350 Camper Special with a Mitchell and Sons Funmobile camper on the back. I am having a problem with my ignition. The yellow wire on the plug that goes to the key has no power. I ran a jumper wire from the batter 12.8volts to this yellow wire and it then in turn makes the truck operate like normal(with the exception of mission dash lights). Without running the jumper wire I have no power at the key and the only thing that works is the horn.
Has anyone had this problem before? I have been through the forum as thoroughly as I could without wasting too much time, as I have already spent several hours tracing wires with no luck.
Also, my brake warning light is on solid with the key on. I am not sure if this is related or not yet. As I have not read into the brake warning system.
Thanks!
Austin
Austin,
The yellow should start at the starter solenoid, (#21 changes to #37 on this schematic) / go through the firewall to the back of the fusebox (where it powers everything) / then powers the ignition switch. Here's a schematic for the 68' that should also apply for your 72. If the yellow wire has a good connection at the solenoid and it looks good going through the firewall it will probably be on the back of the fusebox where it attaches. I'd seen this connection fail more than once. Disconnect the battery and be very careful if you have to unbolt the fusebox to inspect the back where the yellow attaches to the fusebox, (two screws) as the wiring there is usually very fragile.
I'd get past this before chasing down the brake light issue.
Jeff http://www.fordification.com/forum/view ... 22&t=46251
SOLD-71 F-350 dually flatbed, 302 / .030 over V-8 with a "baby"C-6, B & M truckshifter, Dana70/4.11 ratio, intermittent wipers, tilt steering, full LED lighting on the flat bed, and no stereo yet (this way I can hear the rattles to diagnose)! SOLD!
Many Ford bumps / one 76' EB / and several dents through the years.
A lot of "oddball" Ford parts collected from working on them for 34 years now!
2008 Ford Escape 4 x 4
Jeff http://www.fordification.com/forum/view ... 22&t=46251
SOLD-71 F-350 dually flatbed, 302 / .030 over V-8 with a "baby"C-6, B & M truckshifter, Dana70/4.11 ratio, intermittent wipers, tilt steering, full LED lighting on the flat bed, and no stereo yet (this way I can hear the rattles to diagnose)! SOLD!
Many Ford bumps / one 76' EB / and several dents through the years.
A lot of "oddball" Ford parts collected from working on them for 34 years now!
2008 Ford Escape 4 x 4
