Flashing At Temp Code 33

Hey, I'm new.

 

I own a 2000 Legacy L with a 4EAT.

 

I've got a flashing "At Oil Temp" light and after the secret handshake I get a code 33. VSS #2, right? Right. OBD code reads P0720.

 

Upon startup and driving, the car will not shift from first to second until about five seconds of driving above approximately 2000-2200 rpm. After that it shifts, stops, and goes without any problems until the car is shut off and started again. This has been going on for two years.

 

I've replaced the transmission speed sensor harness and sensors from a working transmission and no dice.

 

I've checked the harnesses and in the one going into the firewall I found two wires that seem related to the VSS via a diagram. They had melted their insulation off and were corroded. I found a new harness plug and snipped the wires with plenty of length and replaced the corroded sections of wire and plug. Still no dice.

 

The car has had three or four Dex-III changes.

 

I've pulled out and inspected the instrument panel, the wires in the shift area, and the only thing I've noticed is that the instrument panel drive light doesn't work. P, R, N, 1, 2, and 3 all light up. The D light came on once while on a 1900 mile road trip, and it hasn't come on again since. None of the bulbs appear burned out.

 

Anyone have any ideas?

did you change the trans temp sensor or any of the selonoids? There are 8 selonoids. Doubt it's overheating if the light comes on at start up.

did you change the trans temp sensor or any of the selonoids? There are 8 selonoids. Doubt it's overheating if the light comes on at start up.

 

No, I haven't been able to find good info on what goes wrong or what to check when this specific issue comes up aside from what I've already done. Those sensors and solenoids are located inside the pan, correct?

 

The light doesn't come on at start up, it comes on as soon as the speedometer starts working and stays on in a steady flash.

yeah the temp sensor is in the trans pan.

yeah the temp sensor is in the trans pan.

 

No, I haven't changed it or any of the solenoids.

Is replacing either the temp sensor or one of the solenoids a possible solution to a P0720 and code 33 with these issues?

does your speedo work?

this sounds like a wiring issue.

but if the speedo works, then the speed sensor is working.

does your AWD work?

 

here is how it works, basically. (90 - 99 at least, probably 00 - 04 as well.)

speed sensor is turned by the output shaft on the passenger side of the trans.

it sends an electrical impulse to the speedo.

then the impluses are reduced by 1/4(?) and the signal is sent to the ECU , (and TCU?).

which uses it several ways, but primarily for shift points / speeds in the trans

and for activating AWD, sending more power to the rear wheels.

 

so if the speedo works,

then it could be a wiring issue between there and the ECU or TCU,

or it could be a bad connector pin,

or a bad TCU - VERY RARE!!!! but it could happen, maybe

or a bad ECU - just as rare. but it could happen, maybe

i would check these last unless you have a parts car handy.

 

check you wiring.

check you wiring.

 

Alright, I found a melted green wire in the harness that connects to the transmission plugs and goes through the firewall, along the dash, and to the TCU. According to this chart: http://www.superflow.com/support/supportDocuments/tranxpages/asian/Subaru_4EAT.pdf

the green wire is for shift solenoid 2. My questions are:

 

Does that mean I need to replace the wire and the solenoid?

Also, are there any other diagrams that I can double check the accuracy of this info with?

i would replace the bad section,

and do whatever is needed to avoid a repeat of the damage.

see if it cures the problem.

if yes,

you are done.

 

hopefully you found the problem.

Alright, I've got some pictures in hopes of some identification or links to a wiring diagram.

 

Here are the two burned wires. They are in the main wiring harness behind the heater core. Brown and yellow, and green and black.

http://i1044.photobucket.com/albums/b441/diddleyfhohf/image-3_zpswfqrmwox.jpg

 

The green and black wire is factory spliced here:

http://i1044.photobucket.com/albums/b441/diddleyfhohf/image-2_zpsz5rk3mxl.jpg

 

It is connected to this small plug on the back of the fuse panel under the dash:

http://i1044.photobucket.com/albums/b441/diddleyfhohf/image-1_zps59ynokch.jpg

 

The two wires are in the harness that comes through the firewall and connect to this transmission plug (best picture I could get) on the front passenger side of the transmission:

http://i1044.photobucket.com/albums/b441/diddleyfhohf/image_zpsvgjxruxs.jpg

 

Brown and yellow goes from main plug to unknown, and the transmission connector. Green and black goes to small plug on the back of fuse box, main connector, and the transmission plug.

 

I've been searching for wiring diagrams and haven't been able to come up with anything yet. I am replacing the wires, but I want to know what they go to in order to figure out the reason they shorted in the first place.

Alrighty then.

 

I've replaced the wires in the main wiring harness. Whole dash out, whole dash in.

 

Does anybody know how to test the transmission solenoids?

I hooked up jumper cables to my battery and ran current to the solenoids. The blue lock-up duty solenoid would open with current and close again (I think that's right) without. Same with the red Line Pressure solenoid and the red Brake Duty solenoid. Sweet.

 

The other four are the grey Low Clutch Timing solenoid, the green Shift Solenoid 1, the yellow Shift Solenoid 2, and the black Clutch Timing Solenoid. They function differently, however, as they all seem to be open unless I manually close them by moving the plunger. Then if I apply current, they open again and stay open. Is this normal? Or should they close automatically?