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Tachometer Signal Output

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  1. Peel back ECU connector boot. Attach a voltmeter positive lead to ECU terminal No. 7. Attach negative lead to any good ground. Start engine and check for a steady voltage increase as RPM is increased.
  2. If engine does not run, check engine speed sensors. If engine runs, but voltage does not increase, replace ECU. If voltage increased, but vehicle tachometer did not respond, check wiring between ECU terminal No. 7 and tachometer. If okay, repair or replace tachometer.
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