2001 ABS/Brake Alarm & Light

Hello All,

I just have a couple of questions and was hoping someone could offer some insight.

• 2001 Prius
• 35,240 miles
• 3,000 mile maintenance for life of car

1. The brake light came on. Found out the brake fluid was low - from time to time - very infrequent, fill it up with standard brake fluid
2. Today - ABS/Brake Alarm [very high pitch] went off, but didn't stay on. On/off/on/off...then stayed off

a. Checked brake fluid (it is at max level)
b. Drove car a few miles and the brakes were performing at 100%.

I'm at a loss with what is happening with my car. It appears to be running and braking just as it is suppose to be.

1. Does anyone have any insight on this?
2. Could the central alarm be putting off a false alarm?


Thanks so much,
L&R

 

Just to confirm it really does have 35,240 miles on it. It's been a great little car - really a great performer.

 

Hello and thank you for responding,

There is never any brake fluid on the ground, and fluid is added very occasionally. Perhaps it is burning off? The car is used only for local driving. The greatest distance this car has driven (at one time) in 1.6 years is 45 miles.

The alarm did trigger but the brake fluid level has not changed in 2 or 3 months.

The thing which I find to be perplexing is that the brakes are functioning perfectly. There isn't any delay, intermittent response, no noise, etc.

I did wonder if perhaps it is a random error? I will bring it to the Toyota dealership though. I have been reading the Toyota TIS in relation to this issue in an attempt to trouble shoot this myself.

I am trying to find the logical path to this warning. The alarm did not sound in the second drive around my neighborhood. This is my daughter's car and I just can't take any chances.

 

Hi Patrick,

Thank you so much for all this detail. I think I can handle this, except I don't have a lift here at my house, just a 2-ton jack. If I am unable to, I am going to print out your post and bring it with me to a service center.

To be honest I'm a little put off by the dealer repair centers because the sales associates start calling once they get an idea a car is being serviced. It isn't the case each time, but has been so in the past.

I just took the car out again. The alarm came on right when I turned the car on. It turned off after 5 seconds. I pushed on and off the emergency break, I drove around the block hitting the breaks and then put the car in continuing to drive around the block. I came back turned back on and off the car and the alarm nor lights didn't come on.

Thanks so much for your help,
L&Rs

 

Hi Again Patrick,

Thanks so much for all your help. I have pulled off one wheel but got interrupted with something else. I am going to do one by one and also try to get it scheduled as soon as possible.

I will write back again when I have a solution.

Thanks again,
L&R

 

Hi Patrick,

I brought the car in today. They isolated it to two things, neither being brake failure -

1. One of the computers malfunctioning(?) It is under 100% warranty and they ordered it today....or.......
2. If it is not the computer, then it is likely an actuator (I did read something about that on the TIS Toyota website yesterday.)

They reassured me that her brakes would not fail anytime in the near future. They also confirmed that there was not a leak.

I am hoping it is the computer (For some reason I cannot find the paper they gave me and what codes came up - and I'm searching everywhere for it.). The replacement for the actuator be expensive (as I was told). I really do believe they will do everything they can to solve this with item number 1.

Thanks,
L&Rs

 

Hello Again,
We just went to today to get the ECU replaced. This is the exact explanation:

1. Customer stated check engine light came on - Parts On Order
   
2. P0300, C1202, C1251 and C1259 malfunction in the HV ECU
3. Replaced HV ECU
4. Cleared Codes
5. Drove car and no new codes reappeared.

Parts - #89890-47030/Computer A24

This repair was covered at 100% warranty which was really shocking to me. The mechanic spent about 3.5 hours today assuring it was working correctly. This is in addition to the original assessment.

Anyway, we used 3 (pints?) of break fluid that was put in the car since it was purchased October 2007.

The alarm didn't sound once on our way home. We were told to wait a while to see if the alarm sounds again. They said they believe the ECU solved the problem. If it is not the ECU than they stated it might be an "actuator", but are hoping the ECU solved the intermittent alarm.

The car now has 36,200 miles on it, is garage kept, no rust, dings and maintained every 3k miles. Do you think we are okay now?

 

Hi Patrick,

There might be another issue here. My daughter is a new driver and was heavy on the breaks for a while, sort of like my Mother with her Avalon. I had to teach her to not be so hard on them and to take the foot off the gas to slow down as well. I know this is a little issue, but the car sat for 6 to 8 months before we purchased it. The first owner was ill for sometime and then passed away. He did baby this car, keeping records all the way down to every oil change it has ever had (although it wasn't too many because it had very low mileage). Anyway that is a side note.

We haven't added any break fluid in a few months now and it is at the normal level. They said just as you said about when the break pads wear, but didn't seem to think there was anything wrong with them.

Do you think it could be an actuator issue? Why would any of these things fail with such low mileage and being garage kept?

 

Thanks Patrick,

You know it does trouble me that they never took off the wheels to look at the brakes? Shouldn't they look at the brakes (like you suggested) even thought the codes were saying or suggesting something else? I did mention the brake fluid when I brought the car there, but was lead in another direction.

The alarm has gone off the last two mornings (30 seconds upon starting it) and then never comes back on the rest of the day? I checked the brake fluid and it is holding the same.

Again the strange thing about the brake fluid going down when it did, there was never anything ever...not even a spot or stain of fluid on the garage floor. I'm still not comfortable with this.

The replacement of an actuator is apparently expensive and I'm not convinced it needs to be replaced because a 30 second alarm is sounding. The brake fluid has to mean something.

Thank you,
Vera

 

Hi Pat,

Thanks so much for this reply. I'm so sorry I only just saw it now.

The brakes completely failed yesterday and it was extremely frightening.

It is getting towed to Toyota now. The place where it I brought it to initally said it was having complete ABS failure or ABS module has failed. They also said they put fluid in the car and it came right out. I'm so upset. I am going to call back Toyota now because it is on its way there.

 

I don't understand how a Toyota with extremely low mileage could be having such total failure when it has been babied and garage kept. Now I'm wondering if I should have went ahead and bought her a brand new Corolla last year.

 

Patrick,

I looked up those two part numbers - 89890-47030 and it is a Computer Assy - H.v. supply 2001 per https://www.trademotion.com/shoppingcart/index.cfm?action=viewCart&siteid=213804 and the 89981-47063 is a module.

It appears that both are used on a 2001 Prius? Is the first one a full assembly and the second a module in the assy? If this is the case, wouldn't the module be replaced within the "entire" assembly?

Thank you,
L&Rs