4AGE20V Blacktop ecu diagram

This is my first post in 2017. After long time in my folder, it's time to share with you. Please use and abuse it.

Below is original diagram which I found from Russian forum.

And here is diagram which I've translate into English.

How to diagnose toyota OBD1 error code

1- Turn off engine
2- Go to DIAGNOSIS box and (using wire) jump TE1 and E1 terminal
3- Put IG switch to ON
4- CEL (check engine light) will blink
5- Count and record the blink frequency, example blink 1 time, pause, blink 4 times, pause, and repeated. The error code is 14.
6- If blink frequency cotinuesly without pause, there is no error code stored in ecu
7- To reset the error code, took out EFI fuse for 10 minutes and put back
8- Repeat step 1 to 6 to check if it already reset error code
9- Take your car for a spin and repeat step 1-6 again to check if there still error occur

Jumper Diagram:- 

TUTORIAL VIDEO :-

Error Code Lists:-

Tags : 4age 20v bad idling vacuum gauge oil pressure, 4age 4age20v 20v silvertop blacktop ecu pinout wiring diagram, How to diagnose toyota OBD1 error code toyota 4age,

Lots of ISCV picture

Car engine wash and engine idling

Hi, in this thread I'll write about relation between car engine wash with engine idling.

As we all know, many 4age suffer from bad idling. That happen to me as well.

After being to wash engine last saturday, the bad idling seems has been ok. I dont know what has happened, but idling is better than before.

Before this, I had to use microcompressor to avoid idling drop and engine stall. Then after wash the engine, idling seem to be very high. 2000 rpm when a/c turn on.

I have to turn off microcompressor valve so lower the idling. I suspect there is vacuum leak after the engine wash, but vacuum gauge seem ok. At 19 mm/hg at idle.

My oil pressure gauge also affected. Before this, the gauge will go to max after turn on engine. Now, it operate normally.

Hope this will be permenant solution.