Pulled Transmission, now have High Temp Trans Warni

We did the dreaded back of the engine coolant pipe replacement. All went smooth and we pulled the transmission as part of the process. Prior to pulling, I drained 3 qts from its well as the antifreeze (1 gallon) per Toyota instructions. Put back together. Added 3 qts of trans fluid and topped off the radiator (squeezed upper rad hose etc).

Upon starting the truck, I get a flashing high temp transmission fluid warning flashing on the dash (truck is cold, no leaks underneath). I’m assuming the coolant and atf “pump” on the passenger side of the transmission has some air in it and is giving me a false warning.

Any ideas? Truck goes into R and D and moves but the changes are a bit jerky. Is there a bleed procedure, or should I pin open the trans cooler to get things moving?

Thanks.

 

Sure you didn't pinch a wire or something?

 

I don’t think we pinched anything, though entirely possible.

 

I bought the bleeding funnel set from Amazon to bleed the coolant.

$20 EPAuto Spill Proof Radiator Coolant Filling Funnel Kit

https://www.amazon.com/dp/B01I40ZQWE

 

Thanks - I have a vacuum bleed system but didn’t use it this time. Not sure there any any pockets that air bubbles get caught in.

 

Have you let it idle in P or N and let the trans and engine get up to temperature? Pretty sure the trans has a sort of thermostat and won't fully move fluid until it's warmed up. Part of the reason you check fluid level between a certain temperature range.

I'd get it up to temp without putting it in gear. Then follow procedure for checking fluid level.

 

Haven’t let it in idle as it flashes up the high temp warning maybe 15 seconds after starting it from it sitting overnight. Ran the gear selector thru the range but didn’t want to let it run too l9ng in event something is truly over temp.

I have done the fluid check level previously….5k miles ago when I did a flush and trans filter. This time around 3qts on the dot came out so I put in 3 QTs of new WS fluid and wasn’t planning to check the level.

 

you have a connection off, misplaced, or a wire cut, if it comes on within seconds of start up. Ski

 

You should obviously check the transmission fluid level at the correct temp to make sure it is filled properly. That said, if it’s flashing high temp 15 seconds after a cold start something else is clearly wrong.

 

Yeah it can't be over temp 15 seconds into start up. I'd double check connections as mentioned. Then proceed with warmup and temp check. But that's just what I would do. I don't want to be responsible for you blowing up your trans.

 

Thanks all - will be happy to check the fluid level once I sort out the warning… it’s a pretty quick process.

 

I would check your electrical connections because yes, the warning that quick doesn't seem right along with typically sensors read in a range and a wide open circuit or a short will produce the extremes for their readings. I don't know how this sensor is wired up so I can't predict if it's shorted out or wire broken but I would say it's one of the two. Check all around the bell-housing for wires and look for any forgotten plugs

 

You probably miss a plug for the trans temp senor or some sort.

I replaced mine the weekend before, though I have a manual trans, the wiring plugs were not as straight forward.

 

Thanks everyone. Ended up being the main harness that plugs into the transmission… the “lever” on it was not secured and it was therefore not fully engaged. Fixed 7 trans dtc’s.