About TSS Malfunction message.

Welcome to PriusChat. Adding TSS-P is an ambitious project, and I’m impressed that you would attempt it. I imagine I’m not the only one here who will want to know of your progress. It’s possible that there are needed settings or firmware changes that can only be done by Toyota in the factory, but here are a few thoughts:

When the TSS-P parts were connected:

Did you do the three initialization procedures in the Repair Manual?

1. Engine/Hybrid System: Cruise Control: Front Camera: Before Starting Adjustment
   Engine/Hybrid System: Cruise Control: Front Camera: Adjustment (Sequential Recognition)
   
   
2. Engine/Hybrid System: Cruise Control: Millimeter Wave Radar Sensor: Adjustment
   
   
3. Vehicle Interior: Pre-Collision: Pre-Collision System: Initialization
   (Steering Sensor Zero Point Calibration)

For the first two procedures, you’ll need a Toyota Techstream diagnostic system and some Special Service Tools, Reflector C (09870-60040) and the Base Stand (09870-60010, sold in the 09870-60000 kit).

Perhaps the error messages were reporting that the Forward Recognition Camera and Millimeter Wave Radar Sensor hadn’t been initialized, and that the TSS-P features wouldn’t work until this had been done.

Did you scan for DTCs, and if so, which ones were reported?​

After the TSS-P parts were removed:

Which DTCs are being reported?

Have you tried disconnecting the negative terminal of the auxiliary (12-volt) battery for a few minutes, to reset all of the ECUs?

It’s possible that the Combination Meter, HV Control ECU, etc., have flags in non-volatile memory that record whether they have ever been able to communicate with any of the TSS-P ECUs. If the flag indicates that they have, then they may be likely to report “Lost Communication” DTCs like U023A or U1104.

Indeed, these flags might be shown in the Data Lists—on my car, for example, the Combination Meter has a parameter called “Radar Cruise System” that is shown as “With,” and another parameter in the Hybrid Data List called “DSS Control Status.”​

 

Hi we’re you able to fix the problem I have the same issue I did purchase a tech stream and did a diagnostic witch code C1AA9 shows up there is a tsb for that code but dosnt provide the specs on the sizes of the recognizing images.

 

If you have a 2017 Prius built for sale in the U.S., where Toyota Safety Sense-P is standard equipment, you probably don’t have the same problem as @KOH Jim, who was trying to add TSS-P to a car built without it.

That said, I assume you’re referring to bulletin T-SB-0184-17, “Toyota Safety Sense Front Camera Optical Axis Learning Information.” As the bulletin states, the procedure for forward recognition camera optical axis learning, including the dimensions of the target and a printable example, is in the Repair Manual (more info), under Engine/Hybrid System: Cruise Control: Front Camera: Adjustment (Sequential Recognition). Keep in mind that it’s not just the size of the target that’s important; you also need to display it in the correct locations in front of the vehicle, as the procedure explains. I mentioned an additional hint for this in a previous thread.