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lx50sdn · 08-05-2004, 18:54

Bonehead move .. in performing the EEC diagnostic, I jumped the test connector pin to a two pin connector rather than the self-test input (STI) connector. Big surprise, the CHECK ENGINE light is now on and it ain't running too well. Does anyone know what that two prong connector is in the same harness as the diagnostic and STI connectors?

Any help is much appreciated,
Chris

Aussiblue · 08-06-2004, 05:14

Auto Trans Self Test Ouput. What trans is it? I suspect you now have a dead ECU.

lx50sdn · 08-06-2004, 14:48

Thanks for the quick response. I had the same feeling; the eec diagnostic doesn't even run. Can you recommend a good site to find a replacement. Also, any idea on the likelihood of damage to the trans through the other connector?

Thanks,
Chris

lx50sdn · 08-06-2004, 19:07

Also, is there any sure-fire method of determining whether or not its dead. I know it is providing some voltage and realize it is likely bad but is there a way to know for sure?

Thanks Again,
Chris

Walkinshaw · 08-06-2004, 22:16

id be checking fuses/fusable links before i baught a new ECU / TCU!!!

Aussiblue · 08-07-2004, 08:08

I assume you have a 6 cylinder and LE 85 trans wich has a seperate transmission ECU (or TCU). Hopefully you haven't destroyed both the engine ECU and the Trnsmission ECU.

Aussiblue · 08-07-2004, 08:22

There's a ECU schematic here: http://www.austincc.edu/cloud/images/unk.zip

lx50sdn · 08-07-2004, 17:26

The engine is the 5.0 with an AOD overdrive 4-speed. I hadn't heard a reference to the TCU before the posting but assumed there may be something I could damage since the leads on that connector were hot. I was at my favorite junkyard today for 3 hrs looking for a match (for the ECU) with no luck. My numbers are E8SF-VA; anyone got one laying around they'd like to sell? I am gonna check out that graphic next. The ECU will not cycle through its diagnostic routine though so it must be bad. Hopefully, it absorbed all of the damage and the sensors are OK.

Still working on it,
Chris