Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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ISC Motor


1. Disconnect ISC servo connector.
2. Using a suitable ohmmeter, check continuity between terminals 1 and 4 of ISC motor coil on 1988 models.
3. Resistance should be 5-35 ohms at 68°F.
4. Apply 6 volts DC or less between terminals 1 and 4 on 1988 models, of ISC motor connector, then check that servo operates.
5. If tests are not as specified, replace servo assembly.