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vwnewton
vwnewton, ASE Master and L1, Gm,VW,European
Category: Volvo
Satisfied Customers: 660
Experience:  Numerous years in European auto repair. You name it, I can help!
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1985 Volvo 240 DL: the 2.3l engine (and is it a 240, or a 244, anyway

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This is for a 1985 Volvo 240 DL with the 2.3l engine (and is it a 240, or a 244, anyway??). How does one check the ignition coil to see if it's good? Same for the control unit. And does removing the wiring harness from the control unit really damage the harness to the extent that a new one must be installed? Many thanks!!

The car is a 244 in the US. The ignition control unit(ICM) is a common failure point and the wiring also. The connector is quite hard to get off and the terminals can get spread easily. Carefully remove wire retainer and pull straight down. Look for a spread connector and corrosion. A test light is a quick test on the coil. Ground the test light and touch it to the positive terminal, key on it should lite up. Now put the test light lead on the positive battery terminal and touch the negative lead of the coil, when cranking it should flash the light dimly. If it passes these tests the coil is likely faulty. If the negative of the coil doesnt flash the lite, test the ignition module connections as follows :

Terminal 2 (Blue wire) B+
Terminal 3 (Green wire) B+
Terminal 10 (Black wire) Ground
Terminal 9 (Black wire) Ground

Terminal 5 would require a labscope to test this lead. A square wave sent by the Hall effect sensor. A logic probe can test the low output signal by flashing leds.

If the above powers and grounds are there, the most common problem is a Ignition module. The hall effect sensors fail but not nearly as often as the ICM.

If one of the powers is missing look at the fuse panel and battery connections.

Let me know if this helps, Jason

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