Electrical System goes Dead at Start

[lakesurfer]

1993 F350 7.3L IDI Vin C Turbo, 5-speed:

May I please get the group's opinion on troubleshooting and possible solutions to this problem?


Current Symptom: When I turn the key to start, the entire dash goes dark and not even the solenoid clicks.

Can a failed alternator cause this symptom?

What I've done recently:
* Replaced the starter due to failure.
* Replaced the fender solenoid (Motorcraft).
* Charged the batteries (2 year old Motorcraft BXT-65-850's)
* Pulled the batteries and had them tested at O'Reilly & at Autozone - both showed good and at 100% charge.

How I got here:
* Starter began to be hesitant to turn over, "clicking" at first attempt, then starting OK.
* Third time this happened, after a 30 min drive, the truck would not start. The power connnection terminal at the starter was apparenly melted off, and the cable hanging. Under that hole in the starter, were cooled puddles of previously molten copper.
* This is why I replaced both the solenoid and the starter. The fender solenoid was the Motorcraft part.

So, again:

Current Symptom: When I turn the key to start, the entire dash goes dark and not even the solenoid clicks.

Can a failed alternator cause this symptom?

What else would the group suggest, please?

 

[DaveBen]

Dirty connections to the Battery or Starter. Check those first and then check your fuse box. Make sure all connections are clean AND you have good and clean ground connections.

 

[O-Ring]

Agreed. Sounds very much like a battery connection issue. I haven't had to mess with the starter on mine but if the starter has its own ground wire, check that connection first since you've had the starter out and replaced. Also, least maintained connection is usually batteries to frame. Worth checking.

 

[lakesurfer]

Problem solved (I think): It was the Ignition Switch. Cheap fix.

Thanks to all. Taking your advice about connections and grounds, plus being nagged by that voice in my head that needed to know why my starter MELTED, I dug into the electrical diagrams to locate the grounds and find the root cause.

As I studied the schematics, it all came back to the "ignition switch", which is a bizzare, multi-function switch under the steering column, that is actuated by the mechanical turning of the key.

Turns out it is super easy to remove, inexpensive, and once I searched this forum for "ignition switch" members report it to be as much of a piece of crap as the Ford headlight switch. My local O'Reilly had 2 in stock. I bought the "expensive" Standard brand Ignition Starter Switch (part number US216) for $28.99.

Truck works great now, and a faulty ignition switch seems to explain both failures:

(1) On my last drive, before my starter melted, I believe the switch somehow failed such that it was feeding voltage to the start circuit all the time. Then, every time I pressed the clutch to shift, that voltage drove the fender relay and starter, all while I was at 70 MPH.

(2) Probably, the only thing that saved me from a fire was that the ignition switch start function probably burned out along the way. Hence, when the fender relay and starter were replaced, and batteries recharged, turning the key to "Start" made the whole truck go dead.

Now the truck seems to start, run, and charge reliably again.

If I tear into the old switch and discover anything I may post those results.

Here is a YT video (not of me) that I used to learn how easy this part was to replace:

xc_hide_links_from_guests_guests_error_hide_media

 

[Big Bart]

This problem is some what common on these aging trucks. The starter solenoid or the ignition switch get stuck and the starter turns into a alternator/generator and cause different challenges. You are lucky as your issues where pretty minimal.

Glad you figured it out.

 

[The_Josh_Bear]

Problem solved (I think): It was the Ignition Switch. Cheap fix.

Thanks to all. Taking your advice about connections and grounds, plus being nagged by that voice in my head that needed to know why my starter MELTED, I dug into the electrical diagrams to locate the grounds and find the root cause.

As I studied the schematics, it all came back to the "ignition switch", which is a bizzare, multi-function switch under the steering column, that is actuated by the mechanical turning of the key.

Turns out it is super easy to remove, inexpensive, and once I searched this forum for "ignition switch" members report it to be as much of a piece of crap as the Ford headlight switch. My local O'Reilly had 2 in stock. I bought the "expensive" Standard brand Ignition Starter Switch (part number US216) for $28.99.

Truck works great now, and a faulty ignition switch seems to explain both failures:

(1) On my last drive, before my starter melted, I believe the switch somehow failed such that it was feeding voltage to the start circuit all the time. Then, every time I pressed the clutch to shift, that voltage drove the fender relay and starter, all while I was at 70 MPH.

(2) Probably, the only thing that saved me from a fire was that the ignition switch start function probably burned out along the way. Hence, when the fender relay and starter were replaced, and batteries recharged, turning the key to "Start" made the whole truck go dead.

Now the truck seems to start, run, and charge reliably again.

If I tear into the old switch and discover anything I may post those results.

Here is a YT video (not of me) that I used to learn how easy this part was to replace:

xc_hide_links_from_guests_guests_error_hide_media

Wow I'm glad it wasn't worse. Jeepers that's not cool at all. Also glad you got it figured out!

 

[Austin86250]

glad you figured it out, a neutral safety switch would also give the same problems

 

[lakesurfer]

This is what my melted starter looked like when I first looked under the truck.

 

[lakesurfer]

And this pic shows the puddles of previously molten copper that dripped from the starter to the asphalt.

 

[Cubey]

glad you figured it out, a neutral safety switch would also give the same problems

The NSS is bad on my F250 but just means there's no backup lights (yep, it takes them out) and it has to be started in N instead of P.