First I would like to thank @jerryb . without your kindly help I can never finish my nav deletion project. Also when I mention 06-07 LC100 here, the production date can be all the way back to later time in 2005. You may want to check your model year to confirm the AC controller part number.
I think I am the first one who really tested the post 06 Nav delete with previous generation LC100 AC controller. The reason why we want to use the older model year's parts is that the correct part for 06-07 AC controller amp (88650-60B80 AMPLIFIER ASSY, A/C 2005-7 only) is very hard to find. You will have better chance to find the ac amp for/from the older models. However, the older model AC amp, NONE of those 88650-60821, 88650-60810 nor 88650-60820, are the direct fit for 06-07 LC100. If you hook them up and change the wires based on @jerryb diagram (post 2003 nav delete how to. - https://forum.ih8mud.com/threads/post-2003-nav-delete-how-to.1036722/), you will not be able to engage the compressor clutch thus no cooling air. You need to make some changes of the controller signals in order to let them work.
pre-06 years AC control signals:
Toyota used to have two AC controller signals sets for many years. One uses AC1 and ACT, the other one uses A/CS and ALED. interesting enough, those two sets are all existed for LC100 platform for different engine/ECM configuration. For 2UZ-FE engine, Toyota used A/CS and ALED sets for very long time. however after 06 year model, Toyota decided to go to AC1 and ACT sets of controller and move the MGC and LOCK signal to AC amp rather than on the ECM. You can clearly see in next two diagrams.
US market, 04 LX470 model:
US market, 06 LX470 model:
The different between them:
1) AC Controller signal, before: ALED, AC/S, TEO; after: ACT, AC1
2) Compressor relay engage signal, before: on ECM; after: on AC amp
3) Compressor lock sensor signal, before: to ECM; after: to AC amp
We cannot do much on 3), but we can change the signals to make the AC basic function work. the controller signals chains are following these:
pre 06:
AC button ON --> AC AMP --> AC/S HIGH --> ECM --> ACLD HIGH --> AC AMP
_______________________________________________________ |-> ACMG LOW --> Compressor relay engaged
06-07:
AC button ON --> AC AMP --> AC1 LOW --> ECM --> ACT HIGH --> AC AMP --> MGC LOW --> Compressor relay engaged
You can see AC/S and AC1 polarity are opposite, thus no direct fit. Also you need to generate the MGC signal to drive the compressor clutch. A simple transistor conversion circuit can be used:
I just used PN2222A for the transistor. The AC works fine after the circuit and the engine will ramp up in idle when AC turns on. However it is still not perfect. I noticed that the AC will just keep running after turns on even reach the temperature. before NAV delete I remember that AC clutch will intermittently stops when cabin reach the setting temperature. but this is something can be tolerant.
For anyone who wants to attempt this approach, please first make sure your AC amp type is ACS/ALED or AC1/ACT since even for early model they may still use either. Then you need to generate/connect the MGC signal by yourself.
I think I am the first one who really tested the post 06 Nav delete with previous generation LC100 AC controller. The reason why we want to use the older model year's parts is that the correct part for 06-07 AC controller amp (88650-60B80 AMPLIFIER ASSY, A/C 2005-7 only) is very hard to find. You will have better chance to find the ac amp for/from the older models. However, the older model AC amp, NONE of those 88650-60821, 88650-60810 nor 88650-60820, are the direct fit for 06-07 LC100. If you hook them up and change the wires based on @jerryb diagram (post 2003 nav delete how to. - https://forum.ih8mud.com/threads/post-2003-nav-delete-how-to.1036722/), you will not be able to engage the compressor clutch thus no cooling air. You need to make some changes of the controller signals in order to let them work.
pre-06 years AC control signals:
Toyota used to have two AC controller signals sets for many years. One uses AC1 and ACT, the other one uses A/CS and ALED. interesting enough, those two sets are all existed for LC100 platform for different engine/ECM configuration. For 2UZ-FE engine, Toyota used A/CS and ALED sets for very long time. however after 06 year model, Toyota decided to go to AC1 and ACT sets of controller and move the MGC and LOCK signal to AC amp rather than on the ECM. You can clearly see in next two diagrams.
US market, 04 LX470 model:
US market, 06 LX470 model:
The different between them:
1) AC Controller signal, before: ALED, AC/S, TEO; after: ACT, AC1
2) Compressor relay engage signal, before: on ECM; after: on AC amp
3) Compressor lock sensor signal, before: to ECM; after: to AC amp
We cannot do much on 3), but we can change the signals to make the AC basic function work. the controller signals chains are following these:
pre 06:
AC button ON --> AC AMP --> AC/S HIGH --> ECM --> ACLD HIGH --> AC AMP
_______________________________________________________ |-> ACMG LOW --> Compressor relay engaged
06-07:
AC button ON --> AC AMP --> AC1 LOW --> ECM --> ACT HIGH --> AC AMP --> MGC LOW --> Compressor relay engaged
You can see AC/S and AC1 polarity are opposite, thus no direct fit. Also you need to generate the MGC signal to drive the compressor clutch. A simple transistor conversion circuit can be used:
I just used PN2222A for the transistor. The AC works fine after the circuit and the engine will ramp up in idle when AC turns on. However it is still not perfect. I noticed that the AC will just keep running after turns on even reach the temperature. before NAV delete I remember that AC clutch will intermittently stops when cabin reach the setting temperature. but this is something can be tolerant.
For anyone who wants to attempt this approach, please first make sure your AC amp type is ACS/ALED or AC1/ACT since even for early model they may still use either. Then you need to generate/connect the MGC signal by yourself.
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