How to Troubleshoot the Ignition System in a Saturn Ion

by Editorial TeamUpdated November 07, 2017

Items you will need

  • Spark tester

  • Ohmmeter

  • Voltmeter

How to Troubleshoot the Ignition System in a Saturn Ion. All Saturn Ions have a distributorless ignition system. Most causes of ignition system problems can't be corrected by a non-expert, but there are a few things you can do to discover a problem's location. It primarily involves checking for sparks on the spark plugs and ignition coils.

Spark Tests

Remove a park plug wire from the plug and connect it to a spark tester. Ground the tester to the engine, crank the engine and look for a strong spark. Repeat for all the Ion's wires.

Check the wire's resistance with an ohmmeter if there was a weak spark or no spark. Replace a wire that measures more than 12,000 ohms.

Disconnect all four spark plug wires from the ignition module towers. Have someone else crank the engine for a few seconds and look for alternating sparks between the towers.

Switch the coil pack's positions if no sparks appear on one of them and crank the engine again. Replace the coil pack if the same pack has no sparks; replace the ignition module if the same location has none.

Proceed with the no-spark test if no sparks appear on all four spark plug wires or both coil packs.

No-Spark Test

Watch the dashboard tachometer for signs of motion while cranking the engine. Proceed to Steps 2 and 3 if there is movement, and Steps 4 through 7 if there isn't.

Disengage the six-pin connector from the DIS module. Turn the ignition switch to "On" and measure the voltage to ground at terminal A (with a voltmeter). Check for a blown fuse or shorted circuit if there is no voltage.

Unplug the five-pin connector from the module, and check the resistance of terminal E to ground. There's an open in the circuit resistance is above 200 ohms and a loose terminal or a faulty module if below 200 ohms.

Measure the resistance between the crankshaft position sensor's terminals A and B. (Disengage the DIS module's five-pin connector first). The resistance should be 700 to 900 ohms.

Remove the crankshaft sensor from the engine if the resistance was off. Check the resistance directly, see if the sensor is still magnetized and check the sensor wiring's continuity. Replace the sensor with any problems.

Test the sensor's voltage if the resistance met specification. Set the voltmeter to the AC volt scale, probe terminals A and B of the five-pin connector and crank the engine. Replace the sensor if it puts out less than 200 millivolts.

Check for voltage at terminal A on the DIS module six-pin connector. Check for a blown fuse or an open/short in the circuit wiring if there is no voltage. The DIS module is at fault if there is voltage and no loose terminals.


Don't crank the engine for more than a few seconds or you could damage the starter. Release the ignition key after a few seconds and pause for an equal amount of time before cranking again.

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