U0073 after jumpstarting dead battery

2019 Tacoma TRD OR Premium

59,089 miles on the clock and is the original owner.

Hi everyone,

I haven't posted here in a while, but I'm trying to locate some CAN wires that are related to code U0073.

Storytime:

The battery died due to leaving the ignition on/key off on accident. My buddy jumpstarted the truck for me and immediately got a Christmas tree of lights. I have an ICON T7 scan tool that I used to run the codes. During this process, it had populated with a steering angle sensor code as well, and after some troubleshooting, I've come across a dead sensor.

I've since replaced the sensor and can see the sensor in real-time working as normal. Now I'm stuck with a U0073 code that will not go away, and based on my research, it's a CAN communication error.

Question:

Does anyone have wiring schematics/diagrams for this code so I can check continuity?

I generally fix my own vehicles, ranging from major overhauls, welding/fabrication, and almost everything. This is my newest vehicle, and it's the most complex due to all of the safety features and the CAN bus system.

 

Before digging into wires, there is one action you can try first. Disconnect the negative battery cable for 30 minutes then reconnect and see if things reset.

Jumper cables can cause surges in both vehicles. I use a

$88 NOCO GB40 : 1000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack, Portable Jump Box, Power Bank & Jumper Cables - for 6.0L Gas and 3.0L Diesel Engines

NOCO GB40 to jumpstart because it is less hostile to a battery.

 

Yep, I've tried that a couple of times. I even left them off overnight. No cigar.

 

I'll add that we didn't jump it with another vehicle but via a jumpbox similar to

$88 NOCO GB40 : 1000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack, Portable Jump Box, Power Bank & Jumper Cables - for 6.0L Gas and 3.0L Diesel Engines

NOCO GB40.

 

Did you connect the Negative cable last and remove the Negative cable first when jumping?

 

(+) on battery terminal first and (-) on a metal ground away from the battery. Reversed during the removal process. I never go directly on battery ground when jumping, whether from another vehicle or a jumpbox.

 

Have you tried to clear with your scanner
You may need Techstream to clear the code.
The code is stored when comm were lost with specific modules - Nav, Brake/skid control and steering

 

With the Icon T7, I can clear all codes. I even attempted with an Autel Maxsys MS908 Pro, both are bidirectional scan tools and should clear just fine. Code keeps coming back, which leads me to believe it fried something. I'm just looking for the wiring schematics so I can backprobe the plugs to ensure they're getting proper continuity.

 

Is c1A50 coming back after clearing?

 

Not initially but it will. That code is tied to U0073 for the ABS system. Currently its disabling traction control, radar cruise, and any collision mitigating efforts like auto braking.

 

here is a list terminal with resistance +diagram

Edit. Ping Dm93 for radar control unit pin outs.
I have old version of service manual