View Full Version : Testing Ignition modules

01-08-2009, 12:23 AM
OK I have a 93 Eclipse 2.0 NT with intermittent spark on occasion,..sometimes it will not spark at all. I have checked everything in the ignition circuit and came to the point of testing the Ignition Module. The Haynes book says to use a 1.5v battery with the NEG connected to the GRD on the module and the POS connected to an IB,...then you check for continuity between the GRD and the corresponding OB. It says with voltage supplied there should be continuity and when you disconnect the battery, no continuity. I am getting 7 Mohms with battery connected and 46Kohms with battery disconnected!! I am therefore getting BETTER continuity with battery disconnected!! 46 kilo OHMS against 7 mega OHMS. I thought,..fine I will go fork out $180 for a new one. LO and BEHOLD it tested exactly the same. HAYNES appears to be wrong or both my NEW and OLD ignition modules are bad. HELP

01-08-2009, 04:58 PM
Hi yatipope,

You are using terminology that's different than what's used in the Haynes manual, as far as the component name (module v. power transistor) and the terminals used for testing goes. I've checked the Haynes procedure against the factory service information as well as two other professional-level information sources and it matches exactly. The factory service manual (as well as the other sources) specifies the use of an analog voltmeter, as our illustrations show.

Also, a testing procedure like this will not necessarily be of any use in diagnosing an intermittent no-spark problem. Intermittent problems are no fun because they don't always show up! It's usually necessary to perform the checks when the problem is present. The fact that your power transistor is checking out the same as the new unit seems to indicate that it was OK when you checked it. It's highly unlikely that the new one is defective also.

01-10-2009, 12:17 AM
Well I am still baffled about my 93 2.0 NT eclipse. Sometimes it starts up fine and other times, usually after it has warmed up and then sat for a little while, it stumbles badly upon startup and sometimes won't fire at all. When it does run, a timing light reveals missing spark from all four coil wires. Coil wires for 2 and 4 seem to spark about half the rate of 1 and 3 but all four occasionaly miss as the light stutters. I even checked it with another timing light and it does exactly the same thing. I have replaced the plugs, coil wires, ignition module and checked/cleaned ALL grounds. I am getting concerned it may be the ECM. I guess I will first check the crank/cam sensor. Any other ideas? Thanks