VSC, ABS, (!) and emergency brake light on

So I'm having similar problems with my 07 prius. I did a code check and it said something about the inter cooling pump. Would this problem also cause the car to turn off (out of ready mode) wile driving? This has been happening to me my 12v battery seems to be fine. Any input is appreciated

 

Yes, if the inverter coolant pump failed then the car will stop running after the inverter overheats.

 

Hello everyone,

I have been having this problem for a long time. I have a 2008 Prius, about 160,000 miles. Hasn't been in an incident at all. After driving it a couple of miles to school, I started to notice the vehicle breaking hard at low or even high speed just with a slight touch on the brakes. I took it to the Toyota dealership and was told code C1345 TOYOTA - Linear Solenoid Valve Offset Learning Undone. In addition, they told me that I needed an ABS Actuator assembly.

Before I tried to get that fixed, we tried calibrating the car, bleeding the brakes but nothing. So, for our last solution, we finally got it replaced. Cost thousands. Once this was done, LIGHTS WERE STILL ON and CODE was still present. All they could tell me was "we can try to test something else" costing me $300 more. JUST for testing.

Although braking is significantly better now, the car still brakes hard when in slowing down for a stop behind a car. (Around 5mph) Or when I stop slowly before going into a street.

I already tested whether I can hear the pump run, I can. Next, I tried the battery.

1. Initial power button pressed. without pressing gas pedal: 12.4V
2. Initial power button pressed. without pressing gas pedal: 11.5 V, fluctuating between 11.9V, 11.5V,11.3V then back up to 11.9 V
3. Initial power button pressed. pressing gas pedal: 13.9 V

If anyone could help, I appreciate it. I don't know what else to do with the car. I need this car to last one more year. I'm in college, I can't afford big breakdowns.

 

Hello Patrick,

I have been having this problem for a long time. I have a 2008 Prius, about 160,000 miles. Hasn't been in an incident at all. After driving it a couple of miles to school, I started to notice the vehicle breaking hard at low or even high speed just with a slight touch on the brakes. The VCS, ABS and brake warning lights all turned yellow and stayed on. I took it to the Toyota dealership and was told I had code C1345 TOYOTA - Linear Solenoid Valve Offset Learning Undone. In addition, they told me that I needed an ABS Actuator assembly.

Before I tried to get that fixed, we tried calibrating the car, bleeding the brakes but nothing. So, for our last solution, we finally got it replaced. Cost thousands. Once this was done, LIGHTS WERE STILL ON and CODE was still present. All they could tell me was "we can try to test something else" costing me $300 more. JUST for testing.

Although braking is significantly better now, the car still brakes hard when in slowing down for a stop behind a car. (Around 5mph) Or when I stop slowly before going into a street.

I already tested whether I can hear the pump run, I can. Next, I tried the battery.

1. Initial power button pressed. without pressing gas pedal: 12.4V
2. Initial power button pressed. without pressing gas pedal: 11.5 V, fluctuating between 11.9V, 11.5V,11.3V then back up to 11.9 V
3. Initial power button pressed. pressing gas pedal: 13.9 V

If anyone could help, I appreciate it. I don't know what else to do with the car. I need this car to last one more year. I'm in college, I can't afford big breakdowns.

 

Is the code that's still present still the linear-solenoid-offset-learning-undone code?

Has anyone ever done the offset learning after seeing the code saying it's undone?

It only takes a couple minutes. I think there's a way with a short wire, if you don't have Techstream. At least there is in Gen 3, so I assume an older gen would have had it too.

-Chap

 

DTC C1345 typically would require initialization of the linear solenoid valve and calibration. If that doesn't work then the skid control ECU should be replaced. (Notice that I did not mention the brake actuator assembly as a suspect area.)

Hence, I think that replacing the brake actuator was unnecessary. However you should now have the skid control ECU replaced.

You potentially could save money by having a used part installed. The repair manual suggests it is necessary to disassemble the instrument panel and remove the steering column for access, so this may not be a simple task to DIY.

 

Yes, the code still present is the offset learning and don't think so. I went to Toyota and a private dealership both told me to get the brake actuator done. I was thinking that was my only option so I did.

How is this done? We do have TechStream.

Thank you, will try that next. I suspected it was unnecessary, but since I took it to the dealership and even a private mechanic they both told me that was the problem. I also saw someone else post on here that they had a similar problem and replacing the brake actuator assembly fixed it for them, I assumed it was also the same.

Will get back to you shortly after doing this.

 

Should be something right there on the Utility menu after you select the brake/skid ECU, should say something like "perform linear solenoid offset learning". I think you need to be parked in a level spot where you can leave the parking brake released without rolling ... the utilities in Techstream usually show you messages about any requirements for starting the procedure. Then you tell it to start, leave the car alone, don't touch any pedals, and it sits there for a minute or so making increasingly loud small "pfssh" noises, and then it's done and stops saying it has to learn the valve offset.

-Chap

 

I was told by the Stealer that the fault was my absence module and would cost over $4k to replace with no guarantee the issue was fixed. Took the car to a local Prius Shop plus and they found the fault was actually the pump under the hood, cant remember the exact name

 

was the absence module defective, or absent?

 

Eventually the autocorrect is going to get so good we just let it write the whole post for us.

Both the absence module and the pump can be issues that some people have, but those are a couple possibilities out of a hundred or so, and the original poster in this thread isn't done ruling out the easy stuff yet.

-Chap

 

No it was fine, I bought a used one on eBay and replaced it myself, still same issue linear valve offset Blah blah blah they couldn't reset the abs system.
The issue was the pump the entire time

 

To the OP, as you do have Techstream, you will also be able to watch live pressure readings and the operation of the pump and see if anything seems amiss there. I would still start by reporting back what happens on your 'learn valve offset' attempt.

-Chap

 

Kinda in the middle with a cap and pink coolant. The pump is behind the drivers side headlight, way down with 2 hoses. The coolant should swirl and the pump and hoses should vibrate. Also to Torque Pro app for android is cheap and not hard to use and diagnose. Good luck.

 

What is a IG1 relay module. I have same issue and believe I need this relay. I can't find this discription on auto parts website s. Or just tell me the part number. 2008 pruis base model. Thank

 

This series of lights just started coming in my 2007 Prius. It started happening just after a wheel bearing replacement. The lights have come on only at high speed (over 70). I may have had the cruise control on at these times as well. Mechanic seems to think it's high-speed and not cruise control related. My mechanic has a great reputation but as a female alone at the mechanic I have some anxiety that if it's related to the wheel bearing replacement process, they won't admit it. They broke some of their tools trying to get to the wheel bearing. They said there was so much corrosion they had to put it on the 2 ton press, whatever that is. Is it possible they are the cause of the lights coming on?

 

Check the tires to make sure:

1. They are all the same size
2. The tire air pressure is correct
3. Tire tread depth is similar across the four tires.

It does not sound like the problem is related to the repair job since it happens only at high speed.

 

Can you explain with more specifics on how to do to the jumping between which specific pins on the female obd port.

 

I found these posts very helpful, so I wanted to contribute our experience, including the solution.

The happened in our 2008 Prius starting in 2017-18.

Over a year or so we would intermittently get the same set of four errors. Invariably we’d turn off the car, walk away (for some reason that was necessary, to get the fob away from the car?), and after a try or two it would go away. The problem was growing increasing frequent.

Dealer inspection #1 ~1 year after first symptoms, but after increasing in frequency: they couldn’t find anything wrong with it. A fluke? $100.

A few months later, increasing further in frequency.
Dealer inspection #2: They found the 12V battery was low voltage, because we weren’t driving it much. They charged the battery and the errors went away. “A low battery can cause funny problems, consider getting a trickle charger.” $100.

Problem started right back up in 1-2 days. Within days it was constant, such that the car couldn’t be driven.

Dealer inspection #3: This time they had their lead mechanic on it, working intermittently over about 2 weeks (while we had a nice new loaner).
The 12V battery was charged, that wasn’t the problem.
I don’t have the codes, but he said they pointed to the Skid Control Unit, with “low voltage” on that line. He was skeptical, but actually swapped the SCU of our car with another car, and the problem persisted, ruling out the SCU (a $2500 part!). They did this part for “free” considering that they had missed the problem the first two times we took it there.
The mechanic asked for permission for a few hours of labor to trace the wiring to the SCU, which I approved.
Tested “Power and Grounds”—no problem.
Then he tried swapping the Main Relay #1 and #2, and the “codes moved”.
He replaced the Main Relay #2 (aka Skid Control Relay), and the problem went away—solved!
They only charged us $380 for parts, labor and tax (the part was only $60), which was either really very gracious and/or compensating for their guilt over not figuring it out earlier.

In retrospect the relay had been slowly failing over the past couple of years. For dummies like me, a relay takes a portion of the 12 volts and sends 3V to the SCU. What was probably happening is that the voltage sent by the relay had been slowing going down, but it would only manifest itself when the 12V battery was running low. When fully charged, the 12V batter was compensating for the decreased function of the relay. The initial voltage tests were either not done correctly or were “close enough” on first inspection but not consistently high enough for the tolerance of the SCU.

I think the takeaways:

1. The relays can fail, and they are cheap to fix if that’s the problem.
2. The codes can be misleading.
3. Unless your mechanic zeroes in on the problem, it can take a lot of labor to fix. They probably spent about 6-8 hours total on the last visit.
4. Follow the voltages carefully.

I hope this helps anyone else who might have this or a similar problem in the future. Good luck!

 

Glad that changing the relay fixed it.

However your description of what relays do is wrong.

A relay is just a voltage activated switch. The simplest relay is a 4 lead device, call those leads A,B,C,D. Apply voltage/current between A and B and it closes (usually) or opens (rarely) the connection between C and D. The only way that a relay is likely to affect a circuit in a voltage dependent manner like you describe would be if the resistance between C and D was steadily increasing, and that in turn reduced the current it passed, and the target device was current driven (and very picky about its trigger level.) That is actually possible though, as the contacts in the switch part of the relay can pit, burn, or corrode which results in more resistance through that path. More often though relays fail so that C to D does not switch reliably, in the worst case, being either always open or always closed. More complex relays may switch more than one line, and in those it may be that just one of the lines has a problem.