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Q: Car won't accelerate past 25 mph

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Car won't accelerate past 25 mph. I accidentally put jumper cables on wrong terminals. When I fix that it started right up but would not accelerate past 25 mph. My mechanic said code showed something blown in computer at a cost of $1200 to repair plus labor of $58. Why would a fuse not have blown to protect this expensive part?don't understand what else you need to know.

My car has 109000 miles.
My car has an automatic transmission.

Hi there:

I think I answered your other question, but if the vehicle can start but won’t accelerate past 25 mph, it’s possible that your vehicle has triggered the "limp mode" activation. By connecting the cables in reverse direction it created a surge in amperage, and the flow of electrical current in the opposite direction; which bypasses any fuses or can trigger multiple warning codes. In most cases it causes serious electrical damage to computer. The limp mode happens when the ECU detects a problem inside the transmission. However, if the battery jump cables were swapped - it could have triggered this setting on your vehicle. Either way, to know for certain, you’ll have to have a mechanic physically inspect the vehicle to determine what damaged actually occurred during the jump start issue you experienced.

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