7.3 overdrive off flashing

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06-18-2018, 08:46 AM

Jesses1999f250

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7.3 overdrive off flashing

So recently my 99’ 7.3 has been acting up when it’s raining outside. A few of the issues are the overdrive “off” light flashes constantly, but no issue with the tranny. The speedometer goes all haywire jumping back and forth, and when I turn the truck off and remove the keys, the AC will still be running until I turn it to the OFF setting.

Again, this only occurs when it’s raining outside... Any idea where this electrical problem might be coming from?

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06-18-2018, 09:13 AM

redford

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Clean or replace the VSS sensor on top of the rear differential.

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06-18-2018, 10:46 AM

Jesses1999f250

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Quote:

Originally Posted by redford

Clean or replace the VSS sensor on top of the rear differential.

I’ll give that a try, thanks!

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06-18-2018, 12:33 PM

Mark Kovalsky

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The flashing OD light means that codes have been stored to tell you what's wrong. We can all guess and you can keep buying parts, or you could get the codes read and then we'd know what's wrong. Your choice.

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