Inspection Procedure

CODE 12 - G, NE SIGNAL CIRCUIT (NO. 1)

PROCEDURE
1. CHECK RESISTANCE OF EACH SENSOR IN DISTRIBUTOR.
- Disconnect distributor connector.



- Measure resistance between each terminal shown.

NOTE: HOT and COLD in the following specifications refer to the temperature of the sensors themselves.

COLD: From -10°C (14°F) to 50°C (122°F)
HOT: From 50°C (122°F) to 100°C (212°F)

G1 Sensor (G1 to G-) resistance:
COLD: 125 - 200 ohms.
HOT: 160 - 235 ohms.

G2 sensor (G2 to G-) resistance:
COLD: 125 - 200 ohms.
HOT: 160 - 235 ohms.

NE sensor (NE to G-) resistance:
COLD: 155 - 250 ohms
HOT: 190 - 290 ohms

- If OK proceed to step 2.
- If not OK replace distributor.

2. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN ECM AND DISTRIBUTOR.
- If OK proceed to step 3.
- If not OK repair or replace harness or connector.

3. CHECK AIR GAP.
- Remove distributor cap & rotor.



- Using Special Service Tool (G1 and G2 sensors) and a thickness gauge (NE Pickup), measure the air gap between the signal rotor and sensor projection (Special Service Tool 09240-00020 for G1 and G2 pickups).

Air gap: 0.2 - 0.5 mm (0.008 - 0.020 in).

- If OK check and replace ECM.
- If not OK replace distributor housing assembly.


INSPECTION USING OSCILLOSCOPE



- During cranking or idling, check waveforms between terminals G1 (G2; NE) and G- of ECM.
- The correct waveforms appear as shown in the illustration.