Electrical - wiring - Switch Problem?

[BBT]

Another day, another problem.

A few weeks ago when I was having the CPS - Valve Cover Harness issues, these relatively minor but annoying symptons arose.

1. The radio no longer shuts off with the key in off as it has always done.

2. My US Gear exhaust brake no longer self-cycles when the key is turned on (It senses ignition switch position for this function.), though it works as usual manually.

3. The in-dash oil pressure gauge stays in its normal on position when the engine is turned off. (If I cycle the key back to run, not start, the gauge drops back to its off position. Cycling the key has no effect on the radio or exhaust brake.)

I first noticed these issues after I changed the CPS and got it running again. Do you think the ignition switch might be the cause? Also I had the batteries disconnected for while, could that have fried something?

I checked all the under dash fuses to see which were live with the key off and which need the key on. Can someone tell me if these results are normal?

1. Fuse# 1 AC Blower - Key on only
2. #2 Wiper - Always on
3. #3 Idle pos. switch - Key on only
4. #4 Buzzer, inst lamps - Always on
5. #5 Airbag - unused
6. #6 Tank sw-keyless entry - Always on
7. #7 Turn signal - Key on only
8. #8 Dome lite-radio mem. - Always on
9. #9 Power point - Always on
10. #10 Gauge lamps - Always on (with headlights on only)
11. #11 Radio - Always on
12. #12 Pwr seats - Always on
13. #13 Brake light - Always on
14. #14 Pwr window - Always on
15. #15 Anti Lock Brake - Key on only
16. #16 Cig lighter - Always on
17. #17 Warn-indicator lights - Key on only
18. #18 Speedometer - Key on only

The radio power is connected to #11, and the Exhaust Brake to #12. Both of these were presumably active in key on only position before all this started.
Are these normal as is, or has something gone horribly wrong?

What do you think?

Thanks,
BBT

 

[JOAT]

Wow, thats a wierd one. My first gues since you didn't mess with the wiring is one of the underhood relays is stuck on. I don't have an EVTM handy, but you could just pull relays till the radio goes off.

Ignition switch is possible, if all key-on stuff stays on.

Wiper and Pwr Window I'm pretty sure should have power key-on only. Sounds like something is feeding back voltage, or you've got a stuck relay.

 

[BBT]

Well, radio on, I pulled all the relays in the underhood fuse box one by one while the band played on - no change. Also tried the two relays in the box next to the underhood fuses.

Are there other places I should check for a stuck relay?

Hope everyone has had a great holiday!

Thanks
BBT

 

[Tbar]

A bad battery/batteries can cause wierd electrical problems like that. Try taking the out and having them checked. If one is bad...........replace both.

Also check your ground connections.

If this is not it.................then I am stumped.


Tbar

 

[BBT]

Thanks Tbar,
Both batteries were replaced 7 months ago and are strong. I’m stumped too.

 

[JOAT]

Disconnect the ignition switch wiring and see what happens.

If that doesn't do it, something likely is shorting hot to key-on somehow. Try disconnecting each device with the symptom one at a time, starting with the radio.

The radio has both key-on power and always hot for memory. Could be an internal malfunction connecting the two.

If you have keyless entry, disconnect that module. If not, I think there is some sort of relay there anyway you can unhook.

Also look into the dome lights, and related wiring and switches. Shorts in there can do wierd things. If you have the explorer overhead console mod, mine shorted internally and caused issues.

If none of those devices are at fault, possible you had a short at one time that melted two wires together in the harness some where.

 

[F250Jockey]

Joat is the resident 'Guru' on here with electrical stuff , so do what he says first.

With that said, let me see if I understand this correctly. One of your problems is your radio won't shut off when the ignition is turned off?

Here's what's throwing me on that one: (#11 Radio - Always on)???
Am I missing something here? -popcorn

 

[WD40]

BBT, Try unhooking both ground batter cables and let them stay off for at least a hour. Then hook them back up. This is just a guess to see if things will reset. Goodluck.

 

[BBT]

OK,
Getting back to the electrical problem . . .

Joat, I’ ve so far not disconnected the ignition, haven’t found a way to it yet. Took off the bottom cover on the steering column but didn’t see any switch wiring. Didn’t have time to investigate further. Is there a connector under the dash for the switch?
Unplugged radio memory and power leads, disconnected exhaust brake and saw no change.
Don’t have keyless entry, where are the module and relay located?
No overhead console, dome and cargo lights and switches all working normally.

F250Jockey

Here's what's throwing me on that one: (#11 Radio - Always on)???

Yeah, me too. I measured the voltage at each fuse with both key on and off and thats what was measured - always on. Shouldn’t be, but it was. Something changed a few weeks ago. What?

WD40
Tried unhooking the neg battery cables for several hours. Nothing changed.

Thanks for all the ideas. If anyone has a link for working on the ignition switch and underdash wiring, send it here. All those wires going to and fro make my head swim!

Thanks,
BBT

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