Do new aftermarket ignition switches work?

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DustyEd

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I may need to replace the ignition switch in my '70 Duster 340. A friend that restores Mopars told me the repop ignition switches are junk and are build wrong from the start, needing modification. Anyone out there to back this up? I really don't want to waste $. Thanks, Ed.
 
Yes. No. Sometimes. Maybe.
Some of them are good, but the truth is that a couple of years ago there was an offshore manufacturer that got the wiring wrong- you had to separate the wires from the plug and reinstall them in the correct positions. Keep your old plug and switch to reference them before you install the switch.
There may have been some other issues/other vendors, but that is the one that I personally am aware of.
 
Thanks Professor.

Has anyone just repaired the interior of their original switch? What's the most common cause of failure (of the originals)?
 
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I replaced one on my 68 Coronet, in the early 90s. It works great but I got it from Napa it may have even been American made it's hard to say that was back when things were still good around these parts
 
Oh something to watch for is 68 or 9 and up have a seperate parking light cir so the front parking lights come on while the headlight are on ( or something like that) where as 67 did not. Also @Mattax ( I think) noted that later models have a built in cir breaker with a higher amp rating ( or something like that)

I know a bit wishy washy
 
Oh something to watch for is 68 or 9 and up have a seperate parking light cir so the front parking lights come on while the headlight are on ( or something like that) where as 67 did not. Also @Mattax ( I think) noted that later models have a built in cir breaker with a higher amp rating ( or something like that)

I know a bit wishy washy
Wake up! Ignition switch, not headlight switch. :poke:
1970 ignition switch is the column. Probably the biggest issue people report is the connector.
 
10-4 on that, already looked it over. There are 3 points of pop metal crimping that retains the plastic body. Looks likely a fellow would break one or two of those while opening up or when re-closing. Then, you would have to anchor the plastic body by some other means.
How 'bout testing the original first.

Simple test for major resistance in switch.
Clip or touch meter leads together - that's zero - whatever it says.
Connect an ohm meter to the feed wire (j1) probably 12 gage red.
Then connect the other meter lead to each of the circuits out and test in the various key positions.

Any resistance that a meter can read is not good.
So if it can't pass that then there's no point in going to a load test.
 
If the common failure is inside the main body, there are 3 points of crimped pop metal that retains the plastic back. Looks likely a fellow would break one or two of the pop metal tabs while opening it up or when re-closing. Then, you would have to anchor the plastic body by some other means, like epoxy, etc.

Has anyone repaired the inside?
 
How 'bout testing the original first.

Simple test for major resistance in switch.
Clip or touch meter leads together - that's zero - whatever it says.
Connect an ohm meter to the feed wire (j1) probably 12 gage red.
Then connect the other meter lead to each of the circuits out and test in the various key positions.

Any resistance that a meter can read is not good.
So if it can't pass that then there's no point in going to a load test.

I will check this out, hopefully tomorrow.
 
Brown Blue Black Yellow
Back position 0 0 .8 0
2nd position 0 0 0 0
3rd position 0 0 0 0
Run position 0 .9 1.3 0
Start position .9 0 0 .8

The above ohm readings from meter Red to red at switch connector socket and meter Black to each of the other colored sockets. Meter Red to meter Black read .8. The 0 readings mean no response. If the meter was set to sound the buzzer when there's continuity, the buzzer sounded where there are readings ( .8, .9, 1.3).
 
Brown Blue Black Yellow
Back position 0 0 .8 0
2nd position 0 0 0 0
3rd position 0 0 0 0
Run position 0 .9 1.3 0
Start position .9 0 0 .8

The above ohm readings from meter Red to red at switch connector socket and meter Black to each of the other colored sockets. Meter Red to meter Black read .8. The 0 readings mean no response. If the meter was set to sound the buzzer when there's continuity, the buzzer sounded where there are readings ( .8, .9, 1.3).
What was the zero?
In other words what ohms did it show when the probes were touched together?
 
The one I bought did not have the Accessory position.... threw it in the garbage and bought a NOS.
 
Relays. The correct answer is relays. At least one for the "run" circuit and a second for the ACC circuit
 
Ok. So with the meter showing 0.8 ohms when the probes touching, subtract that from all of the readings.
Lets go through the measurements with the adjusted readings see and what they tell us.

For reference
1674784064985.png


.............................Ign Start..Ign Run....Acc....Start
_______________ Brown
,...Blue,....Black ,...Yellow
Back, Accessory Only..open, ...open, 0.0 ohms, ...open ..=> Correct and no resistance measurable
2nd, Off & Locked......open, ...open, ...open, ...open..=> Correct
3rd = Off......................open, ...open, ...open, ...open..=> Correct
Run position................open, 0.1 ohm, 0.4 ohm, ...open..=>Correct but resistance, especially in the Access circuit.
Start position............0.1 ohm ...open, ...open, 0.0 ohms..=> Correct although possible resistance to Ign Start​

The connections are being made to the correct circuits and not shorting internally.
Showing 0.1 ohms on this type of meter and using probes doesn't neccessarily mean there is a lot of resistance. I might do a load test if switches are difficult to come by. But the 0.4 Ohms to the switched accessory feed is really high. If the reading is confirmed, that's definately a problem. Switched accessory ( Q2 ) feeds the radio, windshield wipers and washer, heater fan, turn signals and maybe A/C if so equiped
 
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You should NOT waste time critically testing these with an ohmeter, for a few reasons. Check them under LOAD and for voltage drop across the contacts. Wiggle the key to check for intermittent contact

I would "rig" about a 10A load, and please don't ask where to get such a thing easy or cheap. If you have a nearby friendly junk yard, get some old headlights and parallel them up.
 
You should NOT waste time critically testing these with an ohmeter, for a few reasons. Check them under LOAD and for voltage drop across the contacts. Wiggle the key to check for intermittent contact

I would "rig" about a 10A load, and please don't ask where to get such a thing easy or cheap. If you have a nearby friendly junk yard, get some old headlights and parallel them up.
I used the headlight voltage drop test for years on trucks. Ohm meters won't always pickup bad connections and green under insulation. I only used a single high beam incandescent.
 
I'm going put my new one in this weekend. 1972 Dodge Dart. Pull the small black wire. It doesn't do anything. The Orange wire needs that space in the connector.

20230127_191325.jpg
 
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