ABS, and VSC and Brake lights on

See my post #25 here: http://priuschat.com/forums/gen-ii-...eshooting/82162-diy-disaster-need-help-3.html

 

Hi Jon,

Yes, the idea is to count the flashing of each warning light. Just look at one at a time, and see if you can decipher a two-digit code.

 

Hi Jon,

Yes, each code will be two digits long. Pls post the name of the light and the corresponding code(s) produced, as one light may be blinking out multiple codes.

I think that the codes will repeat indefinitely so you may not need to run the test repeatedly, but do whatever is necessary to retrieve all of the two-digit codes. Then I can tell you what they mean.

 

Not good idea to post e-mail addresses in a public forum. Better use PM. Jon or Moderator please remove.

 

Hello,
I am getting the following error codes

(!) 41, 42, 53, 57
ABS 42
VSC 45

I have not noticed a drop in performance, and braking appears to be responsive like normal. The only possible change I have noticed since these errors started happening is that it seems like the brake actuator is a little hyperactive. Also, when the error codes are not showing and I press on the brake, you can hear the brake actuator making a winding noise, and the error codes pop up.

If I do need a replacement actuator, has anyone found a more economical choice than the dealer stocked $1800 replacement part? This seems excessive.

Thanks for your insights!

 

Salvage is the only other option for most Prius parts. See http://priuschat.com/forums/gen-ii-...7-brake-actuator-replacement-in-pictures.html for more info on replacement. At a dealer, you are looking at upwards of $2500 for repair, so finding an independent shop to perform the diagnosis and do the repair with a salvage part is very worthwhile.

 

(!) codes are produced by the ECB portion of the skid control ECU.
41: Low or abnormally high battery voltage
42: Open circuit in IG2 circuit
53: Hydro-booster pump motor relay malfunction
57: Accumulator low pressure malfunction

I don't find 42 in the ABS section, or 45 in the VSC section.

How is your 12V battery? Have you had any no-start problems? If the battery is at all questionable I suggest you replace that first.

Then, I suggest that you test the following four relays: ABS1, ABS2, ABS MTR1 and ABS MTR2. You will need a 12VDC power source and a decent digital multimeter.

Remove each relay, one at a time.

Select the ohmmeter function of the DMM, and short the ohmmeter leads together to see what the reading is. That shows you the resistance of the leads.

Use the ohmmeter to determine which terminals are for the relay coil (you'll probably measure ~100 ohms across the terminals, or so.)

Apply 12VDC to the relay coil terminals.

Use the ohmmeter to measure resistance across the switched terminals. When power is applied to the relay coil you should find ~ 0 ohms resistance, and infinite resistance when power is removed. Buy a new relay if resistance > 0.5 ohms (after taking into account the resistance of the ohmmeter leads.)

After you have verified that all four relays are good, then clear the skid control DTC and try again. If the codes reappear then it is reasonable to expect that your car needs a new brake actuator. Since this is difficult to install and I am not aware of independent Toyota hybrid specialists in your area, I suggest that you have your local Toyota dealer take care of that repair. Good luck.

 

Patrick,

As always, thank you for the insightful information.

My 12v batter was recently replaced, and going through the MFD diagnostic screen, it appears to be cranking out the proper voltage. I have never had any no-start problems.

The step by step instructions for test the relays was very helpful. To apply the 12VDC to the relay I used the jumper terminal in the engine fuse compartment and a short piece of wire to ground to one of the engine bolts. An assistant helped me use the ohms meter.

What i found was that 3 of 4 relays were in spec, indicating near 0 ohms resistance when powered. The final relay I tested was the ABS MTR relay and it at first indicated about 0.20 ohms resistance and then occasionally would indicate 1 ohm (open circuit) suggesting that it is not switching on properly when powered. I will replace this ASAP and clear the codes... with my fingers crossed.

I tried to check the error codes again, but they refuse to remaing blinking now?? As soon as I step on the brake and hear the actuator, they return to solid codes (i assume this is an indication of the code actively being thrown).

I'll refer to a video i took of the codes to see if the VSC of 45 and ABS 42 were accurate.

Thank again!

 

Re: SOLUTION! ABS, and VSC and Brake lights on

Patrick thank you!

With your help I have successfully diagnosed and replaced a bad relay! There are four relays for this system and three of them checked out fine indicating ~0.0 ohms. The fourth threw various ohms readings anywhere from 0.01 to 0.25.

I have read that the VSC computer has no tolerance for voltage fluctuations, so this was clearly the problem.

Hopefully others have found this to be a cost-friendly fix to this perplexing set of warning lights.

To reset the error lights put a jumper in pins # 4 & 13 and press the brakes 8 times within 5 seconds. If the problem is fixed, the lights will all blink in tandem repeatedly. When you turn the car off and remove the jumpers, the lights should go out.

I found that toyotapartszone.com was a great resource in locating affordable parts and have very detailed parts diagrams

 

Unfortunately, my problems have arrisen again with the same symptoms and no easy fix like a busted relay. This time I am getting the following error codes:

(!) 41,53,​

ABS 42​

VSC 45​

I took the vehicle to a mechanic who specialized in Prius. He tested the brake system and confirmed that it does not hold pressure when the brake pedal is depress -- final advisory is to replace the brake actuator. ​

bummer....
​

 

A followup on this thread concerning the few 'mystery' blink codes that can't be found in some editions of the Gen 2 manual (36 on ECB, 42 on ABS, 43 or 45 on VSC): more here.