When engine is hot transmission will not engage reverse

1989 MERCEDES BENZ 300SE
40,000 MILES • 3.0L • 6 CYL • 2WD • AUTOMATIC
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RICHARD CAINES
  • MEMBER
  • 3 POSTS
Does not engage reverse when engine is hot.
Oct 10, 2018 at 12:08 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
It sounds like the transmission is going bad but I would try to replace the engine coolant temperature sensor which could be shorting out when warm causing the issue.

Here is a guide to walk you through the steps and diagrams below to show you how on your car:

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Check out the diagrams (below). Please let us know what you find.

Cheers, Ken
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Oct 11, 2018 at 3:49 PM
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