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1996 OBW- A/T light flashing


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So, The A/T temp light is flashing 16 times consistently every start-up, starting tonight.

 

I have no drivability issues, and don't feel anything wrong. No torque bind noted. Also, putting the fuse in the FWD socket definitely turns it to FWD, and I get a the FWD dash light to come on.

 

I've tried to get it into diagnostic mode to pull the code following the directions attached to this thread, but it doesn't seem to work. Did something change? Is this an OBD2 car where you can no longer pull the codes from the light? I'm not sure when that changed.

 

http://www.ultimatesubaru.org/forum/showthread.php?t=72486&highlight=pull+trans+code

 

If so, how do I go about pulling the code?

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So, The A/T temp light is flashing 16 times consistently every start-up, starting tonight.[...]
The 16 blinks indicate an electrically-related problem with the trans, and that further data is stored in the TCU.

 

 

I've tried to get it into diagnostic mode to pull the code following the directions attached to this thread, but it doesn't seem to work. Did something change? Is this an OBD2 car where you can no longer pull the codes from the light?[...]

http://www.ultimatesubaru.org/forum/showthread.php?t=72486&highlight=pull+trans+code [...]

OBDII isn't the issue; Bserk referred to his "96 Legacy Outback" in the thread you've linked to, and was successful in retrieving the code, so it's likely you should be able to as well. It seems Phase-2 4EATs don't include the code retrieval capability (my own '99 OB doesn't have a wire at pin five of the diagnosis connector), but a '96 should normally be Phase-1.

 

Were you able to locate the under-dash diagnosis connector and ground "probes", and identify pin five of the connector?

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Lets rule out the big nasty first. Do some tight ciricles and see if tyhe car will move under its own power smoothly. This will tell us if this is a "fix it now" or we need to investigate it a bit more. Torque bind gets more expensive the more you drive the car.

 

The other popular reason for the light is a bad tranny temp sensor.

 

There is a procedure here on how to pull the codes from the tranny someplace.

 

nipper

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From the http://www.endwrench.com 4EAT phase I diagnosis&service article:

 

1995-98 Legacy, 1996-98 Impreza,

1996-97 SVX, 1998 Forester, Diagnostics

(OBD -II Vehicles)

The AT Oil Temperature light operates under the following conditions: Ignition switch ON/engine OFF is the bulb check mode, the light remains ON. Normal:

Ignition switch ON/ Engine ON, light remains on for two seconds from engine start.

 

Note: A failure is never reported via the AT oil temp light during current operation.The TCU waits until the next ignition cycle to display the following AT oil temp light condition.Therefore the driver may detect an abnormal driveability condition (fail safe operation) with no AT oil temp light indicating a failure.

 

Abnormal - With the ignition switch ON and the engine running, the light remains ON for 2 seconds from engine start. OFF for 0.25 seconds, ON for 0.25 seconds 4 times, then OFF for 2 seconds. Cycle repeats 4 times for a total of 16 Blinks.

 

Abnormal - ATF Temperature is too high The AT temp light comes ON and stays ON until the ATF temperature returns to normal.

 

Trouble Codes

Trouble code retrieval is similar to previous models, except for grounding terminal # 5 of connector B82 a 6 pole black, right side of steering column. Trouble codes will be displayed through AT Temp light with the following differences. There are 14 possible trouble codes communicated from the TCU.

 

They are displayed in the same format as old fuel system trouble codes, long Flash = 10, short flash = 1. For example: 2 long and 4 short = code 24, Duty Solenoid C. The clear memory procedure is simple and quick, just remove fuse No. 14 for at least one minute.

 

OBD-II Operation Overview

The system monitors components and their operation, conducting continuity and performance checks. The check engine light or MIL illuminates when a code is set into ECU memory. Problems with the 4EAT are communicated from the TCU to the ECU.

 

There are 2 trouble codes that are generated as soon as a problem occurs, turning on the MIL.With 22 others requiring a fault or error during two consecutive trips, before turning on the MIL. A trip is defined as a driving pattern in which test parameters are reached for a given time. A failed trip will be erased if the next trip is a good one.

 

Transmission codes generated in OBD-II have freeze frame information available on the Select Monitor in the fuel system section of data display.

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No torque bind. I did tight turns both in AWD and FWD modes and don't have any problems.

 

I think I realize what I did wrong. When it talked about entering diagnostic mode, I thought it meant plugging the Green connector together under the dash.

 

I take it grounding pin 5 is a paper clip trick? Anybody have a picture/diagram or good descrption of which on pin 5 actually is, and which is the ground pin?

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Also, I suspect that it is one of the sensors because the code will set every single time, even if I did nothing the previous run cycle but idle it in park for a few seconds.

 

I think with duty C and the other tranmission operation solenoids that you have to drive it to 20 mph for a code to set?

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Also, I suspect that it is one of the sensors because the code will set every single time, even if I did nothing the previous run cycle but idle it in park for a few seconds.

 

I think with duty C and the other tranmission operation solenoids that you have to drive it to 20 mph for a code to set?

 

no

 

if the issue clears up on its own, the light will not re-occure.

 

nipper

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#12 in that pic - those two diagnosis terminals - those are grounded wires you can use. You can use your own grounded wire too of course. If they've never been used before, those grounded diagnosis terminals will be taped up into the harness so you have to pull them out; the connector itself might be taped close to the wiring loom too.

 

Some people have however in the past stuck the grounded 'diagnosis terminal' into the wrong connector or terminal and blown fuses.

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Yes both of the diagnosis terminals, #12 in that pic, are ground. They provide two because in some cases you need to ground two terminals to perform functions other than reading the code.

 

I want to make sure I am correct here.

 

I see the black terminal, and I also see in the same area 2 green single wire connectors that in my 1990, put it in diagnostic mode when connected.

 

Are these 2 wires with the green connectors the ground wires, or are there 2 more up there than I need to get free?

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Oh those green terminals. No those aren't the ones the diagram is talking about. You need to locate the black B82 connector, then pull it down and have a look at it. You should see the item #12 in the diagram 'diagnosis wires' taped up in the harness; they have bare little metal silvery pins on the ends of them. You might have to pull tape back or cut it to get at them. Or just use a piece of wire and ground it yourself.

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Hi gcleeton. Maybe you could try the code read procedure in this post to see what the issue is. It's fairly straightfoward.

 

Hi newsance. The factory manual lists a host of voltages and resistances, etc. to check. This code has to do with the TCU telling the ECU it wants to shift, and the ECU telling the TCU it has reduced torque (by retarding timing and other things) so it can shift. edit: (purpose is to reduce shift shock)

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Hi gcleeton. Maybe you could try the code read procedure in this post to see what the issue is. It's fairly straightfoward.

 

Hi newsance. The factory manual lists a host of voltages and resistances, etc. to check. This code has to do with the TCU telling the ECU it wants to shift, and the ECU telling the TCU it has reduced torque (by retarding timing and other things) so it can shift. edit: (purpose is to reduce shift shock)

 

Thanks. Ironically I tried it today, and the a/t light didn't flash at startup, so I drove it to run errands. No light the whole day. My guess is that while fumbling around to find the diagnostic leads, I inadvertently reseated a loose connection or the like.

 

Still, its good to know how to do this, and also that if I get a code 16 again, it isn't mission critical and I can keep driving the car in the short term.

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Thanks. Ironically I tried it today, and the a/t light didn't flash at startup, so I drove it to run errands. No light the whole day. My guess is that while fumbling around to find the diagnostic leads, I inadvertently reseated a loose connection or the like.

 

Still, its good to know how to do this, and also that if I get a code 16 again, it isn't mission critical and I can keep driving the car in the short term.

 

Here is an idea. Sometimes the contacts get ditry and oxidize. Next time it happens, confirm the code. Go to the TCU and ECU. Remove and re connect the main connectors. Usually just doing that will clean them, and that may solve the problem.

 

nipper

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