PLATE GP 3726694 - Caterpillar

Illustration 9 g01978235
305-2391 Spark Indicator (15) End of the spark indicator (16) Location on the tool (17) Clip on the adjustable end of the spark indicator (18) "20" indication on the tool
Turn clip (17) until the tip of the threaded rod (16) is set to location (18) .
Disconnect the ignition wire from the spark plug.
Illustration 10 g01341351
Typical configuration (5) Ignition wire (9) Ground point
Connect the spark indicator between ignition wire (5) and ground point (9) .
Use the ARD Ignition Transformer Primary Status override on Cat ET to turn on the ARD ignition system. The ARD ignition system must operate for 20 seconds in order for a diagnostic trouble code to become active.Expected Result:There are sparks inside the spark indicator.Results:
There are sparks inside the spark indicator. - Repair: Turn off the ARD ignition system by disabling the override. Replace the spark plug. Proceed to Test Step 10.
There are no sparks inside the spark indicator. - Turn off the ARD ignition system by disabling the override. Proceed to Test Step 5.Test Step 5. Check for Spark Voltage at the Ignition Coil Output
Connect the ignition wire to the spark plug. Verify that the connection is tight.
Fabricate a jumper wire with an alligator clip on each end. Make the wire approximately 12 inches long.
Disconnect the ignition wire from the ignition coil.
Illustration 11 g01978227
Acceptable corrosion on the ignition coil output (19) Acceptable corrosion (20) Acceptable corrosion
Inspect the terminal at the ignition coil output. Illustration 11 shows acceptable corrosion.
Illustration 12 g01978224
Typical configuration (4) Engine block ground (15) End of spark indicator (17) Clip on the adjustable end of the spark indicator (21) Ignition coil output (22) Jumper wire
Attach clip (17) to ignition coil output (21) . Connect jumper wire (22) to the end of the spark indicator (15) and to engine block ground (4) .
Use the ARD Ignition Transformer Primary Status override on Cat ET to turn on the ARD ignition system. The ARD ignition system must operate for 20 seconds in order for a diagnostic trouble code to become active.
Turn off the ARD ignition system by disabling the override.Results:
There are sparks inside the spark indicator. Turn off the ARD ignition system by disabling the override. - Repair: The problem is in the wire between the coil and the spark plug. Replace the wire. Proceed to Test Step 10.
There are no sparks inside the spark indicator. - Turn off the ARD ignition system by disabling the override. Proceed to Test Step 6.Test Step 6. Check for Voltage at the ECMNote: In order to get a correct voltage measurement the connector for the ignition coil must be disconnected.
Turn the keyswitch to the "ON" position.
Establish communication between Cat ET and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
Use the ARD Ignition Transformer Primary Status override on Cat ET to turn on the ARD ignition system. Measure the voltage between terminal 109 and terminal 88 on the ECM.
Turn off the ARD ignition system by disabling the override.Results:
The voltage between ECM terminal 109 and terminal 88 is greater than