please explain the diagnostic block

[Dunckel]

I have looked around but couldn't find the answers I am looking for. Can someone explain, or direct me to a website that explains what the abbreviations stand for. For example: +B stands for....Boost?? Or TE1,TE2. And how do you know what to jump where to test for a certain problem. If you want to test to see if you are getting fuel pressure, would you put a jumper in TE1 (Test??) and FP (Fuel pressure??) and then see if the car runs.........err something. Sorry, probably dumb questions, but I'm trying to learn. :dunno: :1zhelp:

 

[RazoE]

side question, mine is full of some beige gunk and shit, but every other supra i've seen has it too..

what is it?!?

 

[Big Wang Bandit]

Deelectric grease

 

[lagged]

I have looked around but couldn't find the answers I am looking for. Can someone explain, or direct me to a website that explains what the abbreviations stand for. For example: +B stands for....Boost?? Or TE1,TE2. And how do you know what to jump where to test for a certain problem. If you want to test to see if you are getting fuel pressure, would you put a jumper in TE1 (Test??) and FP (Fuel pressure??) and then see if the car runs.........err something. Sorry, probably dumb questions, but I'm trying to learn. :dunno: :1zhelp:

when diagnosing problems with your car, you follow the TSRM. the TSRM will show you how to use the diagnostic block when you need it. dont just go sticking random jumpers in there.

example, b+ is BATTERY POSITIVE. e1 is a ground IIRC, so if you were to stick a jumper there you would cause a short and blow something.

so, simply dont do it without knowing whats what.

 

[Dunckel]

so, simply dont do it without knowing whats what.

That's what I'm trying to do. Yup, I do follow the TSRM.

 

[PROJECT N00b]

example, b+ is BATTERY POSITIVE. e1 is a ground IIRC, so if you were to stick a jumper there you would cause a short and blow something.

so, simply dont do it without knowing whats what.

i did that, and blew my EFI fuse. so i switched the horn fuse with the EFI fuse whilst i drove to autozone and got some fuses. upon pressing the horn the headlights would come up. cool sight indeed.

 

[CRE]

The majority of the connections in the diagnostic block are test points which intercept ECU signals (E1, OX1, OX2 TE1, VF1, +B, FP), others include the ECT system (the TT contact), TEMS (TS)... See the TEWD for more info.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?Section=Main&Page=48

E1 is ,more specifically, the TCCS' Computer ground (BTW, E2 is the TCCS' sensor ground). +B and +B1 are both 12v supplies from the EFI main relay. VF1 represents the TCCS' VF diagnostic signal (this operates in 3 different modes), FP is a test feed to the fuel pump (bypasses protection circuitry and the relay and resistor pack)..... yada, yada, yoda....

How you use the diagnostic block varies from one circuit to the next. The TSRM covers when and how to test each circuit.



Here's a HINT; Go to the last page of each section of the TEWD and look for the following among the connector diagrams:



This will show you if the circuit in question has a connection to the diagnostic block.


Oh and by the way, it doesn't hurt to replace the old dielectric grease with some fresh dielectric grease. I know mine was no longer up to the task.

 

[jetjock]

Nice job on that post CRE.

Dunckel: There's a dealer test box that can be plugged into the connector but it's not very useful other than to display everything in one place. I had one years ago but got rid of it. You can do the same thing with just a meter. I only wish the car were OBD-II.

 

[Dunckel]

Thanks CRE. That's what I was looking for.