EZK ignition - Tester Modification
89saab05FILE IN VOL.
S.I. Man. I
SEC. PG.
A-1, B-1 130, 59
Issue: 08/89-1170, 1171
Subject: EZK Tester Modification
Application: M89 900, 900S and 9000S Models
Because of changes in the EZK ignition system of M89 900 900S and 9000S models, the EZK Tester, P/N 83 94 058, must be modified. The modification of the tester is required because there is enough feedback current to cause the knock sensor indicator on the tester to incorrectly show a continuous knocking condition while the engine is running. By adding a diode as described in the modification procedure below, the tester will function correctly on M89 models. This modification will not affect the operation of the tester on -M88 models.
Figure 1:
Parts Required:
Terminal P/N 79 69 231
Terminal P/N 78 29 609
Diode P/N 85 30 966
Procedure for Modifying the EZK Tester
1. Slit approximately four inches of the wiring harness sheathing at the connector end (Figure 1). Pull back the sheathing to provide access to the wiring harness.
Figure 2:
2. Locate the white wire in the harness. Remove a three-inch section of the wire, leaving a pigtail projecting from the connector. Strip back the insulation on both ends of the wire (Figure 2).
Figure 3:
3. Attach the blue insulated terminal (P/N 79 69 231) to the end of the white wire where it exits the harness sheathing.
4. Attach the red-insulated terminal (P/N 78 29 609) to the pigtail on the test harness plug.
5. Connect the diode (P/N 85 30 966) to the two terminals noting the terminal size difference between the two diode connections (Figure 3). Cover the diode with the wiring harness sheath and wrap securely with electrical tape.
6. Test the modified tester by connecting it to a M89 900, 900S or 9000S. Check that the knock sensor LED does not light with the engine idling, but still indicates knocking during acceleration.