No diagnostic mode for fault codes? 1JZ conversion to HILUX (JZX90 ecu/engine)

[Spam_J]

I have a 1JZGTE engine conversion in my Hilux and I wanted to retrieve any fault codes that had been stored as I have a couple of minor running issues. However I can't seem to get my ecu to enter any sort of diagnostic mode.

Simple job I thought - so I followed the well documented procedure of bridging terminals TE1 and E1 terminals on the diagnostic connector in the engine bay - and then back probed terminal "W" terminal on the ecu with a test light/multimeter - nothing. I tested with the ignition off, on and also engine running.

Thinking that maybe something was not connected - I checked continuity between TE1 on the ECU and TE1 on the diagnostic plug - checked out ok.

I even tried a spare ecu I have - same deal.

Any help / advice would be much appreciated - as well as pulling out any stored codes I'd also potentially like to hook up a CEL at some point too.

[dumbass]

take it back to your auto elecky and get him to fix it hehe
yr w terminal is a negative trigger
so make sure your test light is on battery positive one end and the w terminal the other

with ign on w should neg trigger your test light
and then bridge out te1 and e1
it should flash

if u tried 2 ecus then u have dud test light or hooked it up wrong
also its hard to test it with multimeter so better of using test light

[Spam_J]

Thanks for the reply

I actually tested with both a 12v test light and only then a multimeter. Test light was tested working itself as well (on the +ve supply used for trying to pull any CELs).

Terminal W (31) was probed and the other side of the test light was connected to a (tested) +ve source.
-TE1 and E1 were bridged via the diagnostics connector - no reading
-TE1 was then bridged directly from the TE1 terminal on the ecu (33) to E1 in the diagnostics conector in engine bay - no reading
-TE1 was then bridged directly to chassis earth - no reading

I believe I've been pretty thorough and not made and school-yard errors, but I must be missing something?

[dumbass]

maybe w terminal is in wrong spot
ill check my workshop manual and see if its correct pin tomorrow
as they are a pain to go thru

[dumbass]

cant find anything for pin 31
w is either pin 4 or 3 depending on what year the jzx90 is
pin 4 is for 2 row plugs

pin 3 is for the chunky 4 row plugs

[Spam_J]

This is the pinout I've been working from - seems to correlate with what's there already?

http://i1168.photobucket.com/albums/...X/68bde86f.jpg

[George]

try to find TE1 terminal on ECU side. Since yours is a conversion, the diag.connector may be a bit disconnected, depending on who did the conversion

[japlish]

Yup i agree, i just did this on my jzx90 setup in a cressida and had to do it from the ecu end and it worked fine.

[Spam_J]

Sorry for the slow reply - not had chance to revisit this since my last post - thanks for the replies.

Anyhow, got permission from the missus to "play cars" and took a look again this morning. I found that the ecu had a missing pin due to corrosion - thought this may be the reason I couldn't get the ecu into any sort of diagnostic mode, so set about replacing it.

ecu_pin_repair.jpg

Fiddly job, but it worked out fine. The repair cured my starting issue which was a bonus - but made no difference to the problems I'm having getting the ecu to spit some CELS out at me.

Here's a picture of exactly how I'm trying to retrieve the fault codes.

Pulling_CELS_.jpg

I connected TE1 directly to E1 on the diagnostics connector in engine bay (which itself tests to ground) - nothing from test light.

Am I doing something wrong / missing something?

[dumbass]

fk me that ecu looks like it went thru the big brisbane floods 2 years ago hehehe

that broken pin is battery backup so will only cause afew little issues if not there

put a voltmeter from te1 and ground
u should get around 5v which in turn goes to ground for diagnosing and brings on check engine light

if u dont get anyhting then maybe yr ecu is fkt

pull it apart as if pins are correded there is good chance its had water inside in a previous life

[Spam_J]

Yep - it's definitely got a bit moist! Hilux had a slight leak from the windscreen, which has dribbled onto the ecu overtime. Doesn't seem to have affected it though (other than no diagnostic mode!).

I actually had to have the ecu completely apart to do that repair on the pin, no other way to do it that I could see - all looks good inside. And I've also tried a different ecu too (as I have a couple of spares) - same deal with that one - no diagnostic mode.

I'll measure voltage from TE1 tomorrow in the light - and come back with findings.