Reading Fault Codes

Trance101 · Post by **Trance101** » Wed Oct 31, 2007 5:47 pm

Hey guys, I tried to read the fault codes off my ECU the other day but I can't make sense of it...

My ECU looks like this:

Its the one with only one red led, and not a red and a green led like most S13 have (well, that's what I've read anyways...)

I turn on the ignition, turn the screw all the way clockwise and this is what it gives me:

(_ = long pulse, . = short pulse, and | = pause)

Sequence: _ | _ _ | . . . | . . . . | . . . . . | after this the sequence repeats itself

Now, this doesn't make any sense to me... isn't each code supposed to be made up of a set of long pulses, followed by a set of short (representing the two digits of the code)?

Can anyone shed some light on this for me?

veecee · Post by **veecee** » Wed Oct 31, 2007 8:14 pm

it looks exactly the same as all the ones i've seen!!!

are you sure there is only 1 LED in there???

thats wierd dude!!! i didnt even know about a single LED system!!!

maybe open that box up and check that the globe hasnt blown or something!

i know with the Mazda rotary turbo ECU's - we had to open it up, and solder in a resistor between two points in order to get the LED's to work. maybe this is something similar???

Trance101 · Post by **Trance101** » Wed Oct 31, 2007 8:31 pm

Ya, its strange I can't figure it out.

veecee wrote:are you sure there is only 1 LED in there???

thats wierd dude!!! i didnt even know about a single LED system!!!

maybe open that box up and check that the globe hasnt blown or something!

I'l try open the box up 2moro and check, thats a good idea. Maybe the green one isn't working... although, there are definately long and short pulses of the red one. I read this (click) thread over at nissansilvia.com before doing it and some of the guys there also had the single red light, but mine still doesn't seem to give me any proper codes...

Toby · Post by **Toby** » Thu Nov 01, 2007 6:36 am

That looks right. It's giving you the modes that you can select. After it displays 3 pulses, for example, you turn the screw back and it will select mode 3. RTFM

Daniel · Post by **Daniel** » Thu Nov 01, 2007 7:40 am

Tobles is right

veecee · Post by **veecee** » Thu Nov 01, 2007 7:56 am

Toby wrote:RTFM

ROFL!!!

Trance101 · Post by **Trance101** » Thu Nov 01, 2007 11:21 am

Toby wrote:That looks right. It's giving you the modes that you can select. After it displays 3 pulses, for example, you turn the screw back and it will select mode 3. RTFM

... I tired to read the manual for this but couldn't find the right section to look in... still can't actually

Since i couldn't find it in the manual I searched the net and came up with that thread on nissansilvia.com ... I got stuck because people on that forum said that the ECU with only one red light only has one mode... guess u shldn't believe everything u read on forums

Thanks, for the advice tho. I'l try it again... in the correct mode this time

EDIT: Thanks, I was able to read the codes, got codes 13 and 34, Engine Coolant Temperature Sensor and Knock Sensor

Daniel · Post by **Daniel** » Thu Nov 01, 2007 1:35 pm

Eish

with the knock sensor error your car must be running like a "bag'O'shyte"!
iv driven around abit with the knock sensor unplugged, quite a pain.

Had a faulty temp sensor aswell, got a replacement from autozone for R40-R50 i think. Ended up coming from a Nissan Hardbody or something, sorry i cant remember exactly what

veecee · Post by **veecee** » Thu Nov 01, 2007 1:48 pm

IIRC the knock sensor error will turn back timing and make it run kak!

the water temp sensor one will cause limp mode to engage and then you wont be able to rev up past 1500-2000rpm!

Daniel · Post by **Daniel** » Thu Nov 01, 2007 1:54 pm

the water temp sensor one will cause limp mode to engage and then you wont be able to rev up past 1500-2000rpm!

not true, well @least not in my case. It does that with the AFM unplugged though

Trance101 · Post by **Trance101** » Thu Nov 01, 2007 5:44 pm

Daniel wrote:with the knock sensor error your car must be running like a "bag'O'shyte"!
iv driven around abit with the knock sensor unplugged, quite a pain.

My car isn't running too badly... hopefully it only knocking occasionally. I can't hear any signs of knocking from the engine either.

My sx is running very rich tho. Its going in for a full service 2moro and then if thing are still going wrong (most likely) i'l try diagnose from there.

veecee wrote:the water temp sensor one will cause limp mode to engage and then you wont be able to rev up past 1500-2000rpm!

My sx seems to be running ok even with the Engine Coolant Temperature Sensor error... it isn't overheating so, would this mean that the sensor need replacing?

Also, would running 102.6 help stop the knocking?

veecee · Post by **veecee** » Thu Nov 01, 2007 7:47 pm

i was just speculating! i remember this issue when i was trying to find out why my car wouldnt rev up past 2000rpm.

one of the problems i found was that the engine temp sensor was not giving a lekka reading. there could have been two reasons for this:

1. faulty sensor
2. bad engine earth

so i took out hte sensor to check it. the sensor was fine.

when i put it back in, the car started working ok. i figured either the bad engine earth was sorted...

or perhaps some crap had gotten into the thread of the sensor and it therefore had a bad earth by itself.

either way removing it and putting it back sorted the immediate problem, well... not for long because hte long term problem eventually came back.

but thats another long story.

who you "sending" the sx to for a service?

Ero_sennin · Post by **Ero_sennin** » Thu Nov 01, 2007 8:59 pm

veecee wrote:who you "sending" the sx to for a service?

hopefully not Nissan lol

Trance101 · Post by **Trance101** » Thu Nov 01, 2007 10:42 pm

Ero_sennin wrote:
veecee wrote:who you "sending" the sx to for a service?
hopefully not Nissan lol

Haha, no not nissan. I'm taking it to my usual mechanic. I found out that he worked at nissan for 13 years in the past, so he should be the man for the job

Daniel · Post by **Daniel** » Fri Nov 02, 2007 11:27 am

Trance101 wrote:
Daniel wrote:with the knock sensor error your car must be running like a "bag'O'shyte"!
iv driven around abit with the knock sensor unplugged, quite a pain.
My car isn't running too badly... hopefully it only knocking occasionally. I can't hear any signs of knocking from the engine either.

Ja it runs, and if you didnt know your car well you might think its normal ish (a mate drove my car with it unplugged and thought it was moer fast, irritated the crap outta me tho coz i knew there was more). but youl know it when its working again. As VC said it retards the timing