Direct Ignition (DI) Coils - Diagnostic Procedure

91saab02

CATEGORY
Engine

SECTION PAGE
3 9
ISSUE CODE
04/91-0101 340


Subject: Checking Direct Ignition (DI) Coils

Application: 1990- 9000 Models with Direct Ignition


Service Manual Section 2:6, Direct Ignition does not contain detailed information on checking individual DI coils. Complete DI ignition cassette units have been replaced needlessly under warranty when the fault was located in one of the four coils which can be replaced individually.

There is no specific DI fault code for the ignition coils, but the decreased engine performance that is a result of a faulty coil may set related fault codes in the DI or LH systems. A faulty coil can cause symptoms such as misfiring, hard starting, etc. When troubleshooting a DI system problem that appears to be a faulty cassette, follow the procedure below to check the individual coils.

Diagnostic Procedure for DI Coils

1. Remove the cassette from the cylinder head.

Figure 1:

2. Remove the screws securing the black plastic lower section of the cassette and separate it from the cassette (Figure 1).

3. Visually inspect the four coils. Discoloration or signs of oil leakage indicate that a coil is faulty. Replace the coil and clean any oil that has leaked onto the cassette cover using a solvent such as electrical contact cleaner or brake cleaner. Do not use carburetor cleaner!

Figure 2:

4. Using a digital Volt-Ohm Meter (DVOM), measure the resistance through the primary and secondary windings of each coil (Figure 2) to ensure that they are within the specifications listed in below. A coil that does not meet these specifications should be replaced.


DI Coil Resistance

Primary Winding Approximately 0.3 Ohm
(Terminals 1 & 2)

Secondary Winding 880 Ohm +/- 10%
(Terminals 3 & 4)


5. Also check the spark plugs to make sure they are the proper type and have the correct gap. Naturally-aspirated models with DI use NGK BCPR6ES plugs and Turbo models with DI use NGK BCPR7ES plugs. The gap for both types of plug is 1.0 +/- 0.1 mm.


6. As a final check, inspect the rubber sleeve and seal as well as the contact spring to make sure these components are not damaged.


Warranty Information:

For warranty claims on faulty coils, use Failure Coding 34046 along with applicable reason and location codes. The location code will be 1, 2, 3 or 4 depending on the cylinder number of the coil. Time allowance is Operation No. 12315 (diagnostic steps) and 34046 (R&R coil).