Component Testing: Tachometer

CAUTION: Reversing the connection of the tachometer will damage the transistors and diodes inside.

Ensure engine is at normal operating temperature. Connect tachometer to "IG-" terminal of engine check connector. Set tachometer to 4-cylinder range. See Fig 1.

Fig 1: Installing Tachometer
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Start the engine.
Compare the tester and tachometer indications. See Fig 2. If error is excessive, replace the combination meter.

Fig 2: Identifying Tachometer Allowable Error Range