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I just completed my w58 swap in my 97 SC300. It runs perfectly besides some grinding going into 3rd gear. Aside from that I ran into a couple of other issues.
1) My driver side seats no longer select/save seat positions with the buttons on the door.
2) My vents only blow hot air (basically max heat) unless the temperature is set to COLD whether the AC is on or not.
I'm not sure if it's because of the auto harness wiring or if its because I changed my ECU to a 97 SC300 M/T in addition to the swap.
Any ideas, help, and advice would be great. Thanks!
Edit:
I'm not sure if this is the solution to my problem, but for the lines that use to run coolant from the radiator to the auto trans, are the inlet and outlet suppose to be plugged or should the outlet run into the inlet?
Last edited by iTowils; 01-08-19 at 01:40 AM.
Reason: Possible solution found for hot air
Coolant runs to the transmission? I've never heard of that. Are you sure you didn't criss-cross the heater box tubes with tranny cooler lines?
The seat memory has its own computer with the mirrors and tilt/telescoping steering wheel. Sounds coincidental to the W58 swap...either one of those components failed randomly (they all have to work for the memory to work) or you left something disconnected.
Sorry, I meant the transmission cooler lines, which were removed when I did the swap. But in place of where those lines connect at the bottom of the radiator (from the diagram below, it should be the inlet and outlet for the oil cooler) I just plugged each side. Not sure if I was suppose to do that or do something else.
From what I've read so far the seat memory isn't working because there is not a point where my car is in 'P'. So I think if I wired that up, it might work again. I'm just not sure where in the car I'm suppose to wire it.
I haven't messed with the radiator lines on the SC, but what you described sounds right for A/T vs M/T setups on other vehicles. Capping the cooler lines shouldn't be affecting flow anywhere else.
I don't recall if I ever tested whether the transmission needs to be in Park for the seat memory to work -- I don't have stock seats, so it's a moot point now -- but I vaguely remember reading that. If so, I guess you'll either need to fool that signal wire or scrounge up the mirror ecu wiring from a M/T car.
I just completed my w58 swap in my 97 SC300. It runs perfectly besides some grinding going into 3rd gear. Aside from that I ran into a couple of other issues.
1) My driver side seats no longer select/save seat positions with the buttons on the door.
2) My vents only blow hot air (basically max heat) unless the temperature is set to COLD whether the AC is on or not.
I'm not sure if it's because of the auto harness wiring or if its because I changed my ECU to a 97 SC300 M/T in addition to the swap.
I'm not sure about the driver's side seat memory issue. It could be related but I'd have to think on that. There is also a seat memory ECU that could have gone bad.
Personally I would have preferred to keep my memory seating position function but as Joe Diego mentions above there is the MKIV Supra seat option. I went with them for the side bolstering that actually holds you in place on CA's many twisty mountain roads and the lower and more aggressive seating position. They also bolt right into place and are easy to wire up. They are indeed lighter too (an SC driver's seat is 74lbs IIRC). I lost seat memory unfortunately and that nice auto-forward and backward function for better rear seat access.
I prefer my MKIV seats for the reasons above but I think it's all preference. I've taken extensive long distance trips in the the MKIV bucket seats still like them and find them comfy. Some folks like sportier seats and some really like the stock SC/Soarer seats for their much more emphasized comfort and seating position. If you do then there will be a way to regain your seat memory function.
...
Now with your A/C issue... I went through this recently with my GTE swap. It could be a very similar issue with your car. You need to put the A/C climate controller into diagnostic mode by holding down the RECIRCULATE and AUTO buttons and then turn the ignition key to ON (but do not start the car).
The A/C controller will beep and run a system check. It will display any error codes present. If you get code 21 (Solar Sensor) don’t worry about it as that can be tripped if it is night time, if you’re in a garage or even if it is just dusk outside.
If you get a Code 12 it means your outside ambient temp sensor circuit for the A/C is not functioning right or is mis-wired for THAT 97 M/T ECU. So it has to be corrected if that is the issue.
What happens is you have an air temp sensor inside the car and an ambient air temp sensor right in the front bumper. If this is your issue I can go deeper into the electrical specifics but in a nutshell without the proper signal from the bumper mounted ambient air temp sensor the A/C controller doesn’t understand how to regulate the interior air temperature. So it throws a Code 12, throws up its hands so to speak and will only allow the A/C mag clutch to engage and blow full cold air only if you turn the temp dial to full cold.
I know how this needs to be wired in terms of my GTE ECU and it’s not hard to fix once all the wires are checked with a multimeter. My rough guess… which could still be in error until I look at an ECU schematic… is that something to do with switching from auto to manual in ECU’s, even if you are going from 97 to 97… does something a little different with these wiring connections between the auto 97’s and manual 97’s.
It would be really weird if so since this is just an ECU change for the same model year and I could be wrong about this…. but the behavior of your A/C right now to me sounds like a Code 12 issue. Check the A/C diagnostic mode and see what codes it flashes at you.
Thinking on this further it is possible that there is some other very minor wiring difference in regards to auto trans or manual trans that is preventing the normal A/C temperature adjustment with the A/C mag clutch engaging when the dial is set to anything but “COLD”.
It’s late and I’m tired writing this (apologies) but it could also be that: some signal the A/C controller wants to see in regards to the transmission operation allowing for the A/C mag clutch to engage in an Auto 97 is wired ever so slightly differently in a 97 manual…. at least as far as the respective ECUs are concerned. And the ECU wiring is all that matters.
Long and winding post. Will have to think on it in the daylight hours.
If you look at my build thread a few pages back I went through a lot of exhaustive troubleshooting of my own A/C Code 12 issue with the exact same symptoms. The wiring comparisons for the MKIV ECU stuff should be ignored in your case. Just look at the SC300 related notes.
But since my research was for a ’93 SC300’s A/C wiring we’d have to see what, if any, differences there are when going up to a 1997 Auto and Manual.
I performed the A/C diagnostics today and got Code 11 and Code 21. Code 11 is for the In-Vehicle Temperature Sensor Circuit. I just looked through the thread you linked, and some people seem to have the code, but nobody has an answer for it. I don't believe that my sensor is broken because it was working perfectly before I did the swap, but I'm not quite sure.
Also another strange thing I found related to the ECU is that on arrival it came with a RHD bracket, even though the serial code matches the one for a 97 SC300 M/T California Spec. Did they use this ECU in Japan as well?
No Soarer with the 2JZ-GE ever cam optioned from the factory with a W58 so no. That's just our USDM and Canadian SC300's. The only Z30 Soarer with a manual was ever the 1JZ-GTE with the R154.
My guess is that the person who sold the ECU to you had some RHD ECU brackets from an engine swap and threw them on. At this point the desirable parts for these cars have changed hands many times.
The A/C code 21 can be disregarded. In bright daylight you will not have it I am 99.9% sure. The A/C sun sensor is just sensitive.
The A/C code 11 I am not as familiar with but if this represents a failure in the sensor or wiring of the inside air temperature sensor circuit then this would also be reason to cause your A/C mag clutch to default to OFF until the A/C temperature dial is set to full cold operation (ie: no temperature regulation). The Code 11 sensor makes up one side of the A/C controller's temperature regulation system an the Code 12 sensor makes up the other side.
Exactly which wire is different between a 1997 SC300 Automatic and a 1997 SC300 5-speed is the question. And for that we'll need the 1997 SC300 full electrical wiring TSRM. It will not be much to change I am sure but apparently it's crucial.
Assuming of course that for sure the wires for this circuit all have proper continuity and assuming that the inside air temp sensor is in good working order.
There's a step by step procedure for each A/C code, starting with Code 11 on page AC-46, so I'll go ahead and go through that when I have the chance. I'll post an update when I do.
Was able to take a look at it today, and turned out that my ambient air temp sensor wasn't plugged in. I probably forgot when I was doing my interior swap.
Plugged it back in, and everything seems to be working again! So I guess we can conclude that the wiring is still the same.
Only other issue I noticed was that the diagnosis codes are still there; is there a way to clear these?
Excellent! I actually had this happen to me as well, lol. In my case it was the outside ambient temp sensor which I had left unplugged until I went to check it. I had hoped all the A/C wiring was the same.
To reset those codes I think the only way will be to disconnect the battery for about 2-3 minutes and then reconnect it. It might only take just over 90 seconds.
01-07-19, 04:28 PM
Issues after W58 Swap
