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hi all i'm new here and also new to asking questions about my car a 93 rs legacy wagon auto imported from japan to australia.

i've had electrical problems ever since i've had it (5 years now) and often the CEL will come on but it dosn't retain a code.

i know this is a newbie question but should the car retain a memory if the CEL comes on or is it normal for it to come on and not remember any codes?

also one way i can make the CEL come on is to turn on my cruise then put the car in park at which point the revs will start going up and down and the CEL comes on but no codes. another way is if the cruise is turned on before the car is started it will keep cranking over even when it has started.

i've had the car to quite a few people now and am starting to get a little depressed about if anyone will ever find the problems as there are a few. i just love this car i don't want to give up on it even though all my family wants me to

any advice would be great thanks

The ECU stores codes. How are you checking the code?

by connecting the the black cables as mentioned by other people on this site. i've also had mechanics do this with no luck and subaru dealership mechanics try and connect my car to their diagnosis machines with no luck.

no one has ever said to me that its strange that the fault codes are not recordered but to me it seems wrong if the ecu can detect a fualt why would it not log and record it?

i have only ever got 2 codes from my car a couple of weeks ago my mechanic got a code out that he said meant i needed a new TPS. however since then i've been having troubles while driveing at slow speeds where i seem to be slipping gears.

and yesterday i got a code from my idle switch. could this mean that the TPS my mechanic put in is faulty?

sorry for all the questions its just that i find now that everytime i drive my car the CEL comes on but then i get no codes out of it

thanks

Did you try the green connectors? Do you even have them there?

Steve

no i have not tried the green connectors but they are there. i am hesitant to try that before i take it to my mechanic considering at the moment it has a code in it. would doing a d-check effect the code that is in it at the moment?

also is it ok to run in d-check mode often and for long trips because one of the problems i am having appears to only happen after i have been driving for a good 40 mins or so if at all.

when in d-check mode if a fault appears when will it tell you? my guess is that instead of the light staying on constant it will flash the code in the same way as when the two blacks are connected is this right?

also i am still curious if it is normal that the check engine light will come on but then not remember a code. or is this why there is a d-check mode because sometime codes arn't stored but if you can replicate what makes the code occur you can catch it in the act?

Most of the knowledge on this board is about North American Legacies, so what we know about our cars may not apply to yours...

When you check for codes with the black connectors, you're hooking the connectors up, then turning on the ignition, but not starting the car, right? Does the CEL flash on and off steadily or does it just not do anything?

I don't know if a in D-check mode it can go from "all clear" to showing a code. I know the opposite happens sometimes on my car, if the car's cold. It flashes a code for the purge solenoid and then when it warms up it switches to the "all clear" steady flashing.

As far as I know, it's never supposed to turn on the check engine light without storing a code... after all, that's what the light is for! I don't see what turning on cruise would have to do with it, but maybe your ECU talks to the cruise computer more than ours do. Is it possible that the cruise computer has the ability to turn on the CEL, and maybe there's a trouble code stored there?

It shouldn't be a problem to drive in D-check mode for a while. Your fuel economy will probably suffer a little but it shouldn't matter.

"When you check for codes with the black connectors, you're hooking the connectors up, then turning on the ignition, but not starting the car, right? Does the CEL flash on and off steadily or does it just not do anything? "

after the check engine light has come on if i turn off the car and follow the above procedure the check engine light will flash steadily.

"As far as I know, it's never supposed to turn on the check engine light without storing a code... after all, that's what the light is for!"

thats what i have been thinking and if thats the case is it possible that my ECU is faulty?

"I don't see what turning on cruise would have to do with it, but maybe your ECU talks to the cruise computer more than ours do. Is it possible that the cruise computer has the ability to turn on the CEL, and maybe there's a trouble code stored there?"

i don't know if my cruise can store codes or if it is any different to your cars in that respect. anyone i have shown this to has been surprised by it but they all have told me well as long as it isn't doing anything else don't worry about it. The problem is the car is doing lots of other things and all i can think of doing is start by fixing problems i can identify. perhaps if i put in a new cruise comp to eliminate that as the problem.

"Most of the knowledge on this board is about North American Legacies, so what we know about our cars may not apply to yours... "

i understand and appreciate this it's only that i am quite new to trying to understand what my car is doing so i find this forum format easier then questioning mechanics because it gives me a chane to read and digest the info and then respond. compared to times when i have asked mechanics and there answers have been full of info that goes over my head. this way through read through these forums i hope to try and better understand aspects of my car so that i can feel some what informed when i approach my mechanic

Hmph.

Maybe it is a bad ECU... If the static RAM where it stores trouble codes is bad,it might make the ECU forget everything every time you shut the car off.

Oh wait... Maybe the ECU's backup power supply is faulty? On our cars there's a fuse in the in-cabin fuse box labeled "EGI" or something to that effect. It supplies memory backup power to the ECU. If your car's the same way, and that fuse is popped, it seems to me that that could cause the ECU to forget trouble codes when you turn off the ignition.

If that fuse is okay, take a voltmeter and measure the voltage at the ECU's backup power supply pin when the ignition is off. The pin should be the same as on our ECUs:

http://www.graphics.cornell.edu/~v/ecupins/

You should measure full battery voltage at that pin at all times.

Let us know what you come up with...

thanks i'll try those suggestions later tonight.

the only thing though is that it has remembered codes just not everytime the light has come on. is it possible that the static RAM or the back up power supply is an intermitent fault?

Have you tried asking over at http://www.rslibertyclub.org/forums/? I'm not saying Vikash doesn't know his stuff (he does), but they might have some other ideas, as they are more familiar with Libertys.

yeah i found them online last night the reason i ended up here though is because my car is actully a legacy imported from japan not a local liberty.

i"m begining to feel though as if the norther american legacy is different to the japanese import i have.

still they can't be completely different cars so i am sure any suggestions you make from experience with your cars could still hold some truth to mine:)

Ok. Good luck, and I hope you figure it out!