As i see the pathway of current to the coil on my 1979 w123 280 euro, it runs as follows: There is two circuits, a starting and a running circuit. Upon starting 12 volts is fed to the coil, from the wire that engages the soleniod on the starter, and when the engine fires and you release the key, power is then fed trough a coil resistor to the coil, thus bringing down the running voltage to +/- 6 volts, inorder to protect the pionts.

My car has no transistorised nor electronic ignition, it has a set of pions and condenser in trhe distrubutor, the pions connects up with the condenser wire, wich then runs to the coil, and connects to the negative side of the coil.

Power from the ignition is then connected to the positive side of the coil. There is two wires connected to the positive side of the coil, the one wire has constant 12 volts, once the ignition switch has been swiched on, the other wire only has 12 volts while the engine cranks.

From this i deduct that the coil resistor was removed from the running circuit, i can also see were it was, and the wiries that should have connected to either side of the resistor, is no connected to each other.

Now for my question, as i see it there should only be one coil resistor on the running circuit, why then when order parts they tell you, you must have two, a .6ohm and a ..8ohm where must the second one be installed.

ONLY cars with a transistorized system has 2 resistors. You car has only 1 & it should be 1.2 ohm OR 1.8 ohm depending on the coil used...

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Thanx M.B. DOC can the absence of the resistor result in the car pinging, i.e. always 12volts at the coil with no resistor?

Only ignition timing & octane of fuel will cause pinging...NOT how hot the spark should be.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator