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Ian C
03-04-05, 20:59
When things go wrong with engine components, sensors, etc. there is a chance that it's going to be a failure mode that your ECU will recognise. Usually, you'll know something has happened because the MIL (Malfunction Indicator Light, the red exclamation mark) lights up.

The ECU stores an error code so that you can check later what the problem is/was. Rather than requiring a bug diagnostics machine, you can use a simple paperclip, or a short loop of wire. You use this to bridge the connections E1 and TE1 in the diagnostics port ( Location, 4th thumbnail along (http://www.mkivsupra.net/vbb/showthread.php?t=35925) )

For VVTi use Tc and E1 (from this thread (http://www.mkivsupra.net/vbb/showthread.php?p=2063112))

Update - Make sure you have de-immobilised your car! Some immobilisers stop the engine light from flashing.

This makes the ECU flash the orange check engine light (not the red MIL light) when the ignition is switched to position 2. If it's a regular flash then there are no stored codes. Otherwise it will blink a few times, pause, blink a few times, and then give a longer pause. That's one stored code, and the number of blinks is the digit, so:
blinkblinkblink pause blink pauuuuuse

Is code 31. You may have more than one stored code, so it'll work its way through them from lowest to highest. It will then loop back to the start again.

For example, if you had a misfire and you also had a problem with your speed delimiter you may find you got:

blink pause blinkblinkblinkblink pauuuuuse blinkblinkblinkblink pause blinkblink pauuuuuse repeat

Which is code 14 (problem in ignition circuit) and code 42 (No1 speed sensor problem)

These codes are stored indefinitely and only cleared when you reset the ECU in some way (fuse removal, battery disconnect/flatten). This means you may have some red herring codes stored if you are at the initial stages of diagnosing a problem, so resetting the ECU, triggering the problem, and then reading the codes is the best method.

-Ian

markssupra
05-05-06, 21:13
:welcome: mate, sorry to hear you got probs already.:(

If I am reading the manual correctly, fault code 42 is No.1 speed sensor. 2JZ-GE engine

All conditions below are detected continuosly for 8 sec or more.
(a) No. 1 speed signal: 0 km/h (mph)
(b) Engine speed : Between 2,000 rpm and 4,500 rpm
(c) Coolant temp : 80° C or more
(d) Load driving

Trouble area.
No.1 speed sensor
combination meter
open or short circuit in No. 1 speed sensor circuit
ECU

Ian C
06-05-06, 00:23
Dodgy speed convertor/delimiter :)

This is a regular occurence so I don't mind it in the FAQ but if you want to discuss it further please fire up a thread in Technical :)

-Ian

Rowland
15-01-07, 13:23
Hi.

I may have completely lost the plot here but shorting TE1 and E1 doesn't seem to work for me! I have an L Reg UK spec mkIV. When I short them and then turn the key to position 2 I get a couple of seconds of interesting clunking noises from the engine bay and then two constant flashing indicators, the "over drive off" one and the orange engine warning light at the left of the right hand bank of warning indicator lights.
I was expecting the MIL (big red exclamation mark in the centre) to at least flash constantly and more likely give me a bunch of codes. It remained completely constant with no flashing at all...

I'm quite sure I connected up the right terminals as they are marked on the label in the diagnostic port cover.

Any ideas as to what I've done wrong?

Thanks,
Rowland

Ian C
15-01-07, 14:01
It's the orange engine one that you should be looking at.

Jake
15-01-07, 14:36
It's the orange engine one that you should be looking at. It is, but that's not what it says above.
I've noticed a few people being confused by this. I think the first post should be corrected where it says "this makes the ECU flash the MIL when the ignition is switched to position 2"

Rowland
15-01-07, 16:01
Thanks for the help.

Rowland

Ian C
15-01-07, 19:42
Correctamundo, edited and apologies for any confusion :)

-Ian

123tom123tom
22-10-07, 18:36
hi idid what has been said on this post and my orange engine light along with the o/d light just flashes repeatedly what does this mean

madmunky
02-03-08, 16:37
Mine flashing repeatedly too, dont anyone know what that means?

Jazzy
04-03-08, 02:38
Means no stored codes.

merckx
09-02-09, 17:27
wow i have that exact same problem when slowing down at the bottom of a hill too!!! anyone have that page?!


Here are pages EG-686 to EG-688. :)

merckx
09-02-09, 22:15
A member on here kindly made some copies of the workshop manual for fellow members.


BE-71 to 74 , BE is "Body Electrical" are available in the manual below.

http://www.turbosupras.com/pages/pages/technical/jza80/a80tsrm.htm


EG-686 to EG-688 , I couldn't find these in the online manual so I scanned them from my workshop manual.

Ian C
29-11-09, 15:17
Technical questions should be posted in the technical section and not nailed onto an FAQ article, thanks.

Ker-prune.

-Ian