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Testing a Coil
DavidM - 20/9/08 at 02:30 PM

Hi,

Does anyone know of a way of testing a 12v coil with a multimeter, out of the car?

David

Macbeast - 20/9/08 at 03:05 PM

Basic test is measure resistance between the two low-tension terminals which should give a couple of ohms. Between either low tension terminal and high tension terminal is probably about 1000 ohms.

I'm just off to the garage so will check for you.

Macbeast - 20/9/08 at 05:42 PM

Tested
Between low- tension terminals 2.5 Ohms ( will vary depending on whether a ballast resistor type or not )

Between either low-tension terminal and HT terminal 7,500 Ohms (7.5K Ohms)

DavidM - 20/9/08 at 07:15 PM

Thanks,

Tested ok.

David

iank - 20/9/08 at 07:21 PM

Though some only fail when they are hot - symptom is fairly obvious in that car runs fine for a mile or five and then runs rough and stops.

02GF74 - 20/9/08 at 07:31 PM

^^^ wot he said.

lt side 3 ohm = non ballast
1.5 ohm = ballast

HT side is several K ohm. (5-10 K)

DavidM - 20/9/08 at 07:43 PM

I fitted a Bosch electronic distributor, but wasn't getting a spark, so was working my way through it. It turned out the wiring instructions in the Wallage kent crossflow book are incorrect. Switched the wires round and it was fine.

David