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Tach Dead -

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    Tach Dead -

    I Just installed a car stereo amp and my tach died post install.

    I did remove/reinstall the car battery during amp install and did get a little spark when installing .

    I checked fuses 10/21 and PO had put 10A fuses instead of 7.5 but neither was blown.

    I replaced 10/21 with 7.5amp but tach ist still dead.

    I also unplugged my power antenna at the antenna in the trunk since I didn't want it going up and down since I dont use the radio. I plugged that back in in case it was related.

    I don't see any blown fuses.

    Given that I spark'd my battery and had 10 amp fuses instead of 7.5 , any thoughts on how to fix my tach - or do I need to send it in for a fix. I don't have a spare tach to check


    Dont forget fuse 12, check and replace that too.

    If all three of the cluster fuses are good, then you can check for screw damage at the Si board. The technical articles page at my website has a good explanation of the screws that hold the dash trim on, if the wrong screws are used, they will damage the Si board and cause no tach and more issues.

    Lastly, if your screws are OK, fuses are OK, and you do not have a refurbished SI board, you can bet that those 30 year old SI board batteries will not recover being disconnected from power that long so...your SI board will need to be refurbished for your tach to work again.
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