This bulletin applies to 2017-2019 Honda Ridgeline vehicles. Transmission temperature may be too hot on the MID and there may be no related DTCs.
The cause: ATF deterioration causes high foaming and low viscosity. During extended high load driving, ATF will foam and cooler flow rate will be reduced.
Update the PGM-FI software and flush the ATF three times.
Before beginning the repair, make sure that all diagnostic and reprogramming software is updated as follows:
i-HDS software version........................... 1.008.020 or later
HDS software version............................. 3.105.009 or later
Honda ECU reprogramming................... 3.6.0.0
J2534 rewrite version............................. 1.00.0034
J2534 rewrite database update.............. 20230414_2492
Flush the transmission fluid three times. Fluid capacity for is 3.3 US quarts at change. Check the ATF level.
Overfilled transmission level can cause an overheat condition. Cold check at 68 degrees Fahrenheit. Hot check at 185 degrees Fahrenheit. Once the flush is complete, advise that ATF level is critical.
The level is designed to be checked at 176 degrees Fahrenheit. If the fluid level is checked at a colder temperature it will read low or on the bottom dot on the dipstick.
If ATF is filled to the top dot when cold, the transmission will be over-filled, which increases foaming and contributes to the overheat problem.
