Dash/radio lose power on ignition wires

[Ifyasquintitsmint]

Been driving my LS swap for a week now and I’m having an odd electrical issue.

Occasionally my gauges/radio will turn off, and when I test them they are getting 1-1.8v instead of constant 12v to the accessory/ignition wire. It’s gettting 12v to power and has a good ground.

If I leave them for a bit they may or may not come back on when i restart the truck.

I’m surprised by why it’s showing up as 1-1.8V vs none and blowing a fuse. Everything else on the truck is fine, it stumbles a bit when the power dies but it’ll run by itself just fine.

Everything else on the truck will work fine, just gets a bit quiet and dark in the cab.

 

[75gmck25]

It may be the ignition switch out of adjustment, or the rack and rod mechanism has broken. Some of the switch contacts may be only making a partial connection.

The actual electrical switch is mounted on the column about where it goes through the dash. The key switch has a toothed gear on the end, which turns a small rack and moves a rod up and down the column. That rod slides the electrical switch and makes contact to power the cab. The electrical switch can get out of adjustment (loosen and slide it to adjust), or the pot metal rack can fracture and not move the rod correctly. The rack and rod is cheap to buy, but requires quite a bit of column disassembly to replace.

 

[Ifyasquintitsmint]

It may be the ignition switch out of adjustment, or the rack and rod mechanism has broken. Some of the switch contacts may be only making a partial connection.

The actual electrical switch is mounted on the column about where it goes through the dash. The key switch has a toothed gear on the end, which turns a small rack and moves a rod up and down the column. That rod slides the electrical switch and makes contact to power the cab. The electrical switch can get out of adjustment (loosen and slide it to adjust), or the pot metal rack can fracture and not move the rod correctly. The rack and rod is cheap to buy, but requires quite a bit of column disassembly to replace.

That makes total sense, I’ve actually had issues with my ignition switch previously and had to replace it.

Since I have a spare ignition switch on hand I’ll swap that in and see if that’s the cause. Is the switch a on/off switch or is it gradual? I've also noted my rod is slightly bent, I may try to straighten it in the column.

The 1-2v readings are really confusing me as I’ve never had something read that low unless it was due to a low battery.

 

[CorvairGeek]

Make sure you have the correct switch to swap too! Tilt and non-tilt column are different. The rod moves in the opposite direct between columns.

 

[Doppleganger]

Is it anything you can trigger by jiggling the key? I used to have similar issues with cars when the switch was going out.

 

[Ifyasquintitsmint]

Is it anything you can trigger by jiggling the key? I used to have similar issues with cars when the switch was going out.

Just started up the truck to swap vehicles due to snow. Nothing I did could get the dash/radio on.

Trucks running fine, going to throw an ignition switch at it tomorrow night and see if that fixes it.

Pretty confused if it is my ignition switch, why my truck still starts up just fine.

 

[Doppleganger]

Just started up the truck to swap vehicles due to snow. Nothing I did could get the dash/radio on.

Trucks running fine, going to throw an ignition switch at it tomorrow night and see if that fixes it.

Pretty confused if it is my ignition switch, why my truck still starts up just fine.

A retired tech friend of mine used to refer to the ignition switch as a cerebral cortex of power distribution. Lots of nutso things can happen if its buggy.

 

[Ifyasquintitsmint]

Drove it about 150 miles, got back drove to the store and wouldn’t start. No clicking, could hear the fuel pump.

Swapped in a different ignition switch, checked my neutral safety switch, starter was working, battery was good. Didn’t have a volt meter on me, but will break it out tomorrow.

 

[Bessie]

That makes total sense, I’ve actually had issues with my ignition switch previously and had to replace it.

Since I have a spare ignition switch on hand I’ll swap that in and see if that’s the cause. Is the switch a on/off switch or is it gradual? I've also noted my rod is slightly bent, I may try to straighten it in the column.

The 1-2v readings are really confusing me as I’ve never had something read that low unless it was due to a low battery.

The low voltage readings just point to a poor connection, Did you straighten the rod ? and make sure the switch was being pushed all the way? You could have a bad ground- like a braided body ground strap.

 

[Bessie]

The low voltage readings just point to a poor connection, Did you straighten the rod ? and make sure the switch was being pushed all the way? You could have a bad ground- like a braided body ground strap.

Did the truck start?

 

[Ifyasquintitsmint]

Did the truck start?

Nope, I could get the starter to click a bunch, but nothing even attempting to start

 

[Ifyasquintitsmint]

The low voltage readings just point to a poor connection, Did you straighten the rod ? and make sure the switch was being pushed all the way? You could have a bad ground- like a braided body ground strap.

I can try to clean them up

 

[Ifyasquintitsmint]

Had a local guy say the starter solenoid could be bad. Might try testing that.

 

[Bessie]

Had a local guy say the starter solenoid could be bad. Might try testing that.

Could be, and probably is a separate gremlin that just decided to show it's ugly little head but that wouldn't have anything to do with your electrical issue. It was ok before you changed the switch, back track and make sure you didn't screw something up. You may have had a solenoid problem before you changed the switch the first time (intermittent starter operation?). Then you didn't install the switch adjusted quite right. SLOW DOWN!

 

[Snoots]

Starter just clicked? Bad solenoid. Just remove it, take it apart and rotate the input lug 180 degrees. Put it all back together and viola!