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Discussion Starter #1
Hello, I tried to search for solutions everywhere, but with no luck.
I am installing standalone ecu (Ecumaster EMU Classic) leaving stock ecu (to have working all interior gadgets). But after first start-up I noticed that coolant temp gauge doesn't work and oil press/level lamps are 'on' all the time.
I relocated stock ECU to glove box, so I needed to rewire all the necessary wires to it: chassis grounds, engine grounds, ignition, to EFI relay, +12V, all immo related wirres, all A/C related wires, CRK/CAM sensors (with sensor ground), oil press and level signal wires, coolant sensor wire (with sensor ground), both multiplex wires, alternator status wire.
I tested oil press wire if it gets signal from engine (it does). Also my standalone ecu shows coolant temp perfectly (connected parallel to stock ecu). Looks like other gadgets are working (didin't checked fuel gauge so far).
Is there anything that I missed connecting or is this just the unsolvable issues when using this combination with custom ecu?

Thanks in andvance!
 

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Ok, I’m not familiar with the standalone you have but with my AEM Infinity I couldn’t tie the standalone into the stock temperature sensor, if the stock ecu was also connected to the sensor. It would read way hotter than it was and give me a temp sensor error. So I had to get an adapter that let you split the radiator hose and had a threaded hole to install an aftermarket coolant sensor. I’m not sure about your oil light issues, but I bet you have something grounded out since those all operate on a -12v trigger and they’re all on. Probably something in the process of moving the stock ecu to the glove box. Seems like a monumental task.
 

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Discussion Starter #3
Thanks for the tips. Oil press/level lamps are not that simple, because wires from senders goes to ECU. And then from ECU via multiplex (i guess) to body ECU and cluster gauge. I checked if I get signal at the end of the wire on ECU side and it does (circuit opens, then oil press builds up). Im thinking about making these lamps full analog, one contact to +12V and another directly to sensors.
And of course fuel level gauge isnt working also. But its obvious, because Im using MAP sensor instead factory MAF.
 

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Yeah, seems a hot mess. For curiousity’s sake, why’d you move the stock ecu?

The whole mpx system makes doing anything to the car very difficult. I guess it saved Toyota a few wires between the ecu and cluster, though. You’ve got to have something triggering a ground to illuminate all those warnings. I don’t know what else it could be. The oil psi sender is a spring diaphragm that either opens/closes on low oil pressure and sends a ground trigger to the ecu. Same with the oil level sensor - just a “dumb” float that opens/closes with level of oil. Could you have incorrectly placed the sensor wires to the ecu? I’d start by unplugging the sensor - to - ecu wire and seeing what happens.

To get your fuel gauge working, you need to plug the MAF sensor into the charge pipe where it can read. Then clamp it with a zener diode so it doesn’t see boost. Make a IGF simulator and call it good. My fuel gauge reads perfect and true and I have ID1050x injectors and a return fuel with RRFPR.
 

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Discussion Starter #5
I moved ecu because now in its place is throttle body with filter. Thanks for sugestions, I will check wirring diagrams again.
As for fuel level gauge this seems too much trouble only because my air filter ir mounted directly on throttle body (yes, it is NA) and there is no space to do otherwise. And this level gauge actualy works, but only by 1/4 steps, which is good enough to predict when I need to refill. :)
 
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