st205 ecu in mr2 error code 54 help

[monstersw20]

i need to know if anyone ever had this problem. This is a st205 celica gt4 ecu in my mr2 i am getting error code 54 which is intercooler water pump malfunction, does anyone know of a mod to eliminate this code, i have heard of a resistor pack to fool the computer but dont know much more about it if it is true or not please help

[JJ]

Dont think many people have got around this - this is one of the problems the GT4 owers have when they junk the chargecooler and fit a front mounted intercooler !

Sorry, no help - but generally, the ecu is looking for a constant draw from the ecu ( what is used for the chargecooler pump normally ! )

[paul port]

I remember this one...
As said, it's a problem GT4 types have when they loose the pump in favour of a FMIC... Thats why they crave a MR2 Turbo ECU!! as the Rev3 one is pin compat - but obviously does not have the pump circuitry.

The problem is, that as well as the error code... you also get Limp Mode ignition timing! You see, the ECU assumes that the pump is not circulating water through the Chargecooler - therefore it must be getting hot... Of course the ECU should know this anyway as there is an IAT (Air Temp) sensor in the throttle body - Still it has the limp mode so they say.

Anyway... A few years ago, I participated in such a thread on the GT4OC-UK forum... I took appart my own ECU, compared the pinout so they knew a Rev3 MR2 ECU would be pin-for-pin for them... Reverse engineered the missing components on my ECU (As the whole ECU is the same, it's just the pump interface circuit and software are differernt).

I determined that the ECU is expecting some sort of pulse signal from the pump to prove that it is actually rotating - not just drawing current. I offered to design a 'Pump Simulator' if any SW205 owner would let me measure the signals on their car with an oscilloscope, or loan me the pump they had already removed.

Guess what... not a single one offered.

Instead, they all seek either a MR2-Rev3 Turbo ECU, or a Power-FC... and end up sticking their old ECUs on Ebay.

Sorry I won't be able to help without 'testing' a real ST205 or at least getting hold of a pump!!

Paul

[JJ]

Guess what... not a single one offered.

You must have intimidated them paul with your brains and stunning looks !!

I was going to mention to the chap in contacting you for further details as I remember you looking down this route to assist them.

Funny hey, bend over backwards to help and don't want to take the bate.

[psycho]

bump

i buy a power fc for st205 and have the same problem! i

[SFLee]

http://www.6gc.net/forums/index.php?showtopic=60854

as i was looking my charge cooler setup

it may help

[psycho]

i find this:

http://www.mr2oc.com/showthread.php?t=1 ... e+54+st205

i think it's good!