Intermittent Brake, Brake warning, ABS, VSC

Or put the car in ready, park, apply parking brake, and measure if there is significant voltage drop across the cables.

 

Their tool may not have been able to reset the ABS light. Please try resetting the light using the procedure in post #7.

http://priuschat.com/forums/gen-ii-prius-main-forum/73075-how-do-you-reset-abs-light-yellow.html

You can see a diagram of the data link connector here: http://priuschat.com/forums/gen-ii-prius-technical-discussion/30354d1305558989-2004-prius-abs-light-abs2

I still suspect some sort of wiring problem but the possibility of a bad ECU is increasing. The next step if it will not reset is to get a junkyard ECU.

 

C1300 is the result of a failure of the internal self test of the skid control ECU. I think your only option is replacement. The only external influence that might effect this test result is if a power supply voltage going to the ECU is low. That could cause strange problems. Assuming you tried to reset the ECU with the following proecdure, and it still is on, the problem is persistatnt.

CLEAR DTC (When not Using Intelligent Tester)​

(a) Using shorting wire, connect terminals TC and CG of the
DLC3. (pine 4 and 19 of the OBDII connector)​

(b) Turn the power switch ON (READY).

Then check ECU pins:

Tester Connection Condition Specified Condition
S8-7 (IG1) - Body
ground
Power switch ON
(READY)
10 to 14 V
S10-5 (IG2) - Body
ground
Power switch ON
(READY)
10 to 14 V
S8-3 (+BI1) - Body
ground
Always 10 to 14 V
S9-5 (+BI2) - Body
ground​

Always 10 to 14 V

Measure the resistance of the connectors.​

Standard resistance​

2 ​

​

​

​

CHECK AUXILIARY BATTERY VOLTAGE
CHARGE OR REPLACE AUXILIARY
BATTERY​

3 ​

​

​

​

CHECK BRAKE CONTROL POWER SUPPLY (IG VOLTAGE)​

IG
B18​

F047500E01​

Tester Connection Condition Specified Condition
B18-5 (IG) - Body
ground
Power switch ON
(READY)
10 to 14 V​

REPLACE BRAKE CONTROL POWER
SUPPLY​

4 ​

​

​

​

CHECK SKID CONTROL ECU​

GND1
IG1
+BI1
GND2
GND3
+BI2
S7 S8 S9 S10
GND6
IG2
GND5
GND4​

F047485E54​

Tester Connection Condition Specified Condition
S8-7 (IG1) - Body
ground
Power switch ON
(READY)
10 to 14 V
S10-5 (IG2) - Body
ground
Power switch ON
(READY)
10 to 14 V
S8-3 (+BI1) - Body
ground
Always 10 to 14 V
S9-5 (+BI2) - Body
ground
Always 10 to 14 V
Tester Connection Specified Condition
S7-1 (GND1) - Body ground Below 1 ​

​

​

​

Ω​

S8-2 (GND2) - Body ground Below 1 ​

​

​

​

Ω​

S8-1 (GND3) - Body ground Below 1 ​

​

​

​

Ω​

S9-2 (GND4) - Body ground Below 1 ​

​

​

​

Ω​

S9-1 (GND5) - Body ground Below 1 ​

​

​

​

Ω​

S10-4 (GND6) - Body ground Below 1 Ω

 

Yes, import the custom PIDs and you can use HV battery horsepower or regen brake torque.

http://priuschat.com/forums/gen-ii-...-custom-pids-torque-android-app-formulas.html

 

No problem. If you replace the ECU with salvage, it may require zero point programming with a scan tool. Good luck!

 

I also have been experiencing intermittent ABS VSC (!) lights. Happens only at startup and 90% of the time they go off in less than a min. I have replaced the 12v battery, checked resistance on ground, Voltage at acc, on and ready all are within recommended ranges. i have checked all 4 relays for ABS and they are good, checked IG1 relay and its good. had codes read today and they are;
U0073 Control Module Com Bus off
U0123 Lost Communication Yaw rate sensor
U0124 Lost com lateral acceleration sensor
U0126 Lost com steering angle sensor
U0293 Lost com with Hybrid Vehicle control system
Lights have not reappeared in 4 days since testing the IG1 relay (Coincidence?)
cold under 50 degree or high humidity (raining) conditions seem to trigger lights.
I'm hoping one of the experts in this forum can help me with my personal twist on this problem.

 

Has your car been in an accident or experienced flood damage? It appears that you have a wiring harness problem since your DTC all relate to failed sensors and communications with other devices. That problem is very hard to pin down unless you know that a particular area of the wiring harness was damaged, thus allowing you to focus on it for repair.

 

I've only had the car for a year and the car fax was clean but i think it was in a minor front end accident because i noticed a few weeks after buying it the front fenders and hood are slightly different color and i found some bondo on the bottom of one fender.

 

Thought I should revive this topic, any positive outcomes for the above problems? Did the ECU replacement solve the problem?
I also have a problem which I think tracks back to the skid control ECU: the steering angle sensor (SAS) continuously shows a 1150 degree of the steering wheel. If I reset the ECU and drive for 5 minutes to allow the ECU to store the steering zero point, the SAS shows correct readings until I restart the car.
Could it be that the skid control ECU does not store the data after shutdown?
No DTC stored, car is a 2006 Gen2, 100.000 miles.

 

I"m having some similar issues. Any update on this? 2007 Touring trim package