Technical Changing to electric starter

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Technical Changing to electric starter

britbe

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Hello,

I have a 500R 1975 and I want to change the starter to a electric starter. I already have the electric starter & the ignition switch. Now, I need the wiring sheme ;-)

On the ignition switch I have these connectors:
- Double connector with label '30'
- Double connector with label '15/54'
- Connector with label '50'
- Double connector with label 'INT'

On the electric starter I have these connectors:
- Connector with label '50'
- Big nut

See pictures attached. Can someone tell me which connector I need to connect to what? And the cables to use, which thickness should I take?

Thx!

kr
Bjorn
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This standard defines automotive wiring labels: https://en.wikipedia.org/wiki/DIN_72552

15 = ignition switch
30 = battery +ve
50 = starter control
54 = brake light
55 = fog light

On a normal ignition switch, there are 3 or 4 positions: off, accessories (sometimes), ignition and start. Ignoring accessories for now, ignition powers the coil and distributor. Start connects 12V to the coil of a relay whose switch connects the battery to the starter motor.

The starter motor I've worked with in the past had only one connection plus earth. The one connection both energised the solenoid which pushes the starter gear into the ring gear on the flywheel, and also energised the starter motor. On a fiat 500, you will either need to replace the key switch for one with a starter position, or add a push button for the starter.

The Fiat 500 starter motor has a switch built in to it and is connected permanently to the battery. When you pull the start lever, you manually push the gear in to the flywheel. The lever also pushes against the switch on the starter motor. So you have a battery feed. Is the photo of your new starter motor? Perhaps the relay is built in. Terminal 50 would then go to the start button or switch. The big electrical connectors with nuts on them will be fused battery and ground, which the Fiat 500 starter motor already has. It is perhaps best to double check what you have.
 
Thx for your reply!

I have a ignition switch already for a electronic starter, that were the connector in my first post.
On my old switch, see pictures attached, I have the connectors:

- 30
- 15/54
- 30/4

So it's clear that 30 & 15/54 are also on the new ignition switch.
But 30/4 is not on the new switch, do I connect this to 30 or INT on the new switch?

50 on the new switch I need to connect to the 50 on the electric starter.

Which wires are there also on the electric starter? Is there a wire to the coil? to the battery? Where should these be connected to?

kr
Bjorn
 

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I don't know what INT is. Do you have a multimeter? Check for continuity between these pins with the switch in each position. This should tell you which one goes to the battery and which ones go to the ignition and starter. My guess is that 30 goes to the battery, 50 goes to the starter relay, 15/54 goes to the ignition coil. INT may be accessories if your switch has it.
 
I don't know what INT is. Do you have a multimeter? Check for continuity between these pins with the switch in each position. This should tell you which one goes to the battery and which ones go to the ignition and starter. My guess is that 30 goes to the battery, 50 goes to the starter relay, 15/54 goes to the ignition coil. INT may be accessories if your switch has it.
thx, any idea what the connection 30/4 on the old ignition switch is?
 
thx, any idea what the connection 30/4 on the old ignition switch is?

4 is listed as "coil, distributor, high voltage" in the list. Best to check with a multimeter which pin is connected to which when the switch is turned.
 
Update: I've successfully installed the electric starter. Maybe interesting for you all, I will list the old & new connections here:

Old -> New

- 30 -> 30
- 15/54 -> 15/54
- 30/4 -> INT
- 50 -> Only on the new switch, this is the connector for the cable to the starter motor

Many thanks for your support!

grts
 
Not a move I would recommend to be honest mainly because the solenoid operated starter motors are very hard to get in the UK and can be very expensive, as are the spares. Also lots of owners like the originality and quirkyness of the cable pull starter.
 
I agree on the originality part, but I will keep my old starter so I can return to original if I want.
But if I want now that my wife drives with the 500, I need to make it as easy as I can ;-)
 
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