SPC

With some help from this thread and EEPROM programming I was able to add DRCC and PCS to my 2014 US spec. IS350 AWD. What finally worked was pulling the Driving Support ECU & Engine Control Module and virginizing them, which caused the car to think it has a new ECM. Process to get the DSU to allow Radar Cruise (disconnect battery before uninstalling DSU/ECU): 1. Backup ECM and DSU EEPROMs before doing anything. See these photos of the modules: https://imgur.com/a/jU8Jtjv 2. Write the semi-virgin data to the DSU EEPROM. (93LC66 16 bit) See this original and semi-virgin example data for writing. Don't delete the Region information or Part number information. Blank out the information like the example. (Different years and models may look nothing like this). (I'm not 100% sure if this whole step needed) 3. Write all 00's to the Engine Control Module EEPROM (93LC86 16bit) 4. Reinstall virginized ECM and DSU 5. Reconnect Battery. Initiate Immobilizer/ECM learn routine. (Jump Pin 4 and 13 on the OBD2/DLC, Ignition on for 30 minute, then off and start the car 6. Write VIN using Techstream to Engine Control Module (It will show a VIN not programmed DTC). Mine still shows the DTC after writing the VIN, but the check engine light is now off. I'm guess it will disappear eventually) 7. Test DRCC. All seemed to be working well matched leading vehicle speed and braking worked well. No DTC's after 30 min of driving. Radar aiming will likely be necessary to ensure it's properly tracking vehicles in front of you. DRCC should look like this one the instrument cluster: https://imgur.com/a/InCNkBt Notes: Be cautious with the ECM modification, there's always a chance of causing the car not to start if something goes wrong. EEPROM Tools and Guides I used: CH341A EEPROM Programmer I used: https://www.amazon.com/dp/B07R5LPTYM?psc=1&ref=ppx_yo2ov_dt_b_product_details CH431A EEPROM Programmer modifications needed to support 93LCXX EEPROMSs: YouTube Instructions EEPROM editing software I used: AsProgrammer_v2.1.0.13 (Windows driver included in the driver install folder): https://mega.nz/#!VMR0QQhL!wU4fYzCqjtHfXbD_tyOCRVnd3ahGgjprG_8RnVJ7N3o Other good things to watch would be this YouTube video also showing modification of the programmer to work on 93LCXX EEPROMs used in Toyotas. The ECM and DSU both have a protective coating sprayed on the boards, so you may need to gently scrape the pins of the EEPROM for good contact with the programmer. Please keep in mind that I'm not an engineer or an expert, just a hobbyist that enjoys working on cars. These modifications can have expensive/safety repercussions if something goes wrong.