VSC OFF after steering rack replaced

[toyseqdrvr]

Greetings all who have helped with all the VSC issues. However, I have not found a thread yet about the VSC lights coming on after a steering rack replacement. I have 2001 Sequoia 4WD. My local guy did the work on the rack, but could not get the lights out. Any ideas about why the steering rack replacement would trip on the VSC lights?

[JBH1989]

Could be he damaged one of the wheel speed sensors while finagling the rack out, or simply left them disconnected. You can check the connectors and make sure each one is connected. There's a more likely scenario though:

Toyota requires that a Zero Point Calibration be performed whenever the alignment is changed (required when replacing the rack) or whenever certain chassis parts are replaced. Toyota uses a Vetronix Mastertech scan tool (aka the toyota diagnostic tester) to perform this operation. It's likely that your mechanic's scan tool can perform this procedure as well. There's a good chance he didn't know that this needed to be done, but it is part of the job and he/she needs to eat the cost to perform the job (it only takes a few minutes and virtually no labor).

Here's the lowdown from Toyota TSB # 0020-08 (for an 05 Seq)

Repair Procedure
1. Disconnect the cable from the negative (-) battery terminal for MORE THAN two (2) seconds.

2. Reconnect the cable to the negative (-) battery terminal.

3. Perform the applicable zero point calibration of the yaw rate sensor and/or the steering angle sensor.

HINT
Refer to the applicable TSB or Repair Manual for the zero point calibration procedure.

4. Re-initialize all applicable systems available on the vehicle (power window sunroof power lift door etc.).

This requires a REAL bidirectional scan tool with enhanced Toyota functionality, not a standard generic OBD-II code reader. If he/she doesn't have one, there is a procedure posted in a different TSB that may or may not work without the tool. Apparently it's mainly used to monitor the data PIDs to confirm the repair. Hopefully one of the Toyota specialist techs will post if the signal check mode is essential.

What year is your Sequoia?

For an 03+:

1. Whenever replacing the Skid Control ECU, registration of the new ECU must first be performed.

A. For 2WD models: Registration is complete. Go to step 2.

B. For 4WD models:

a. Vehicles with Transfer Lever: After turning the ignition switch ON, with the shifter in the "P" position, move the transfer lever to the "L4" position.

Vehicles with Push Button Selector: Place the vehicle in NEUTRAL, press the "L4" button, and then place the vehicle in the "P" position.
b. At this time, the VSC system buzzer will sound for 3 seconds indicating that registration is complete. Now turn the ignition switch OFF. Go to step 2.

NOTE :For the 2001 - 2002 model year Sequoia zero point calibration procedure, refer to TSB No. BR001-02, "VSC Related Zero Point Calibration and Sensor Check."

2. Perform master cylinder pressure, yaw rate, and deceleration sensor zero point calibration.

A. Connect Diagnostic Tester to DLC3.

B. Move the shift lever to the "P" position.

C. Turn the ignition switch to the "ON" position.


D. Place the Diagnostic Tester into Signal Check mode under the ABS/VSC menu.

E. Keep the vehicle in a stationary position on a level surface for 4 seconds or more.

F. For 2WD models: Press the TRAC OFF switch 3 times within 3 seconds without pressing the brake pedal.

G. For 4WD models: Press the center differential lock (TRAC OFF) switch 3 times within 3 seconds without pressing the brake pedal.


H. Check that the VSC buzzer sounds for 3 seconds.

NOTE:If the VSC buzzer does not sound:

^ Repeat the zero point calibration procedures listed in Step 2.

^ Check the VSC buzzer circuit.

I. Zero point of master cylinder pressure, yaw rate and deceleration sensor is complete. Go to step 3.

3. Perform steering angle sensor zero point calibration.

A. Disconnect the Diagnostic Tester.

B. Calibrate the steering angle sensor by driving the vehicle above 28 mph (45 km/h).

4. Confirm zero point calibration.

A. Stop the vehicle.

B. Place the shifter in the "P" position.

C. Connect the Diagnostic Tester to DLC3.


D. View the ABS/VSC Data List to see that the steering angle value changes when turning the steering wheel.

5. Disconnect the Diagnostic Tester and turn the ignition switch OFF.

[toyseqdrvr]

Hi JBH1989, YOUDAMAN!! I have a 2001 Sequoia SR5 4WD. Is there any way you could widdle down your directions for the 2001? My local mechanic has a real big heart...so the simpler the better for him. I do not think he has the Toyota diagnostic tester, though. Is the VSC inoperable while the lights are on in this case?
Again, many thanks!! I'll keep you in the loop. Have a good weekend.

[JBH1989]

He probably has a SnapOn brick or Solus or an OTC or something. If he has the enhanced functionality for Toyota, he probably could do it. I'm blessed with 5 generic Mastertechs with the factory cards, so I've never tried it on another. I'll try it with a Solus Pro on Monday and see if it can.

Yes, vehicle stability/traction control will be disabled.

Here's the procedure: It mentions that Signal Check must be used or codes will be set, if it were me I'd try to do it without and clear the codes after. If that failed, then use the Toyota tool. It's up to your mechanic though. I don't want to whittle it down since I have NOT performed this procedure myself, I cannot properly determine what may or may not be essential information.

Calibration Procedure

Prior to calibration, all ABS and VSC DTC codes must be cleared.
1. Clear all ABS and VSC DTC Codes.

A. Connect the Toyota Scantool to the DLC3.

B. Turn the ignition switch ON.

C. Operate the Toyota Scantool to erase the codes.

2. Perform Zero Point Calibration on Sensors.

A. Enter "Signal Check" mode on Toyota Scantool (after verifying connection, go to "Trouble Data," then to "Signal Check").

B. All remaining steps must be completed before exiting "Signal Check" mode or additional codes will be set.

NOTE:
^ Perform calibration on a level surface.

^ A new VSC ECU is set to be used on a 2WD vehicle. If the VSC ECU is being installed on a 4WD vehicle, use the following procedure to set the ECU for 4WD use

^ If VSC ECU is being replaced on a 4WD vehicle:

^ Turn the ignition switch ON, with transmission shift lever in the "P" position. Then move the transfer shift lever to the "L4" position. The transfer shift lever must remain in the "L4" position for steps 2C - 2F

^ When the VSC ECU has recognized the vehicle as a 4WD, the buzzer will sound for 3 seconds. This recognition and buzzer will occur only the first time this procedure is completed after the VSC ECU is replaced.

^ After this procedure, it will not be possible to install this VSC ECU in a 2WD vehicle.

C. Ensure transmission is in the "P" position.

D. Turn the steering wheel at least 5 degrees in each direction. Then hold the steering wheel straight ahead (0 degrees).

E. Press the VSC OFF (or TRAC OFF) switch 3 times within 3 seconds.

F. The VSC buzzer should sound for 3 seconds.

3. Perform Sensor Check.

A. Check that the shift lever is in the "P" position. Check that the steering wheel is at 0 degrees.

a. Check that the ABS warning light and VSC TRAC warning light blinks.

b. Keep the vehicle stationary for at least 4 seconds.

B. Check the Deceleration and Yaw Rate Sensor.


a. Shift the transmission into the "D" position and drive the vehicle at approximately 3 mph. Turn the steering wheel 90 degrees or more to the left or right and complete a "U-turn" (180 degrees).

NOTE:
^ When completing the U-turn, the ending position should be 180 degrees +/- 5 degrees of the starting position.

^ Do not spin the wheels while performing this check.

b. The VSC buzzer should sound at the beginning of the turn, indicating the completion of the deceleration sensor check.

c. Stop the vehicle and shift the lever to the "P" position.

d. On a 4WD vehicle, the VSC buzzer should sound for 3 seconds, indicating the completion of the yaw rate sensor check.

C. Check the master cylinder pressure sensor.

a. Keep the vehicle stationary for at least 2 seconds.

b. With the transmission in the "P" position, do not apply any pressure to the brake pedal for at least 1 second.

c. Press the pedal with at least 147 N (15 kgf, 33 lbf) for at least 2 seconds.

d. The VSC buzzer should sound for 3 seconds indicating the completion of the master cylinder pressure sensor check.

D. Check steering angle sensor.

a. Turn the steering wheel left or right to full lock position. Hold for at least 1 second, then turn the wheel to the opposite full lock position and hold for at least 1 second.

b. The VSC buzzer should sound for 3 seconds indicating the completion of the steering angle sensor check.

E. Check wheel speed sensors.

a. Drive the vehicle straight ahead at or above 28 mph for several seconds. The ABS warning light will temporarily stop blinking when this speed is reached, and stay off until the vehicle approaches 0 mph.

NOTE: It is not a problem to drive the vehicle through turns prior to step E.a. Therefore, it is not a problem to exit the parking lot, etc. in order to perform wheel speed sensor check on a street.

b. Complete "Signal Check" by pressing "ENTER" on the Toyota Scantool. Disregard any codes while in "Signal Check" mode.

4. Check ABS and VSC DTC Codes.

A. Re-initialize the Toyota Scantool to the vehicle and check for trouble codes.

B. Refer to the Toyota hand-held tester operator's manual for further details.

C. Turn the ignition switch OFF and remove Toyota Scantool.

D. Ensure that the vehicle is in 2WD mode prior to returning it to the customer.

NOTE: If at any time during the sensor check procedure, the appropriate buzzer does not sound, check the VSC buzzer circuit according to Repair Manual procedures.

^ 2001 Sequoia Repair Manual, Pub. No. RM832U1, page DI-321

^ 2002 Sequoia Repair Manual, Pub. No. RMB86U1, page DI-332

I'll call my dealer buddy on Monday and see how much a Zero Point Cal would cost if you went in. I'll also check my price on the service and see if there is any difference. We'll often take BMWs to the dealer to get programmed since we don't have the capability, and get a discounted price. Your mechanic might be able to do the same if necessary.

[toyseqdrvr]

Hi JBH1989,
Just got a call from an indy toyota specialist that I found locally who was unable to reset the VSC lights because the steering angle sensor /clock spring needs to be replaced. ? due to steering column being toyed with during rack replacement or just bad luck, no one knows. $779.00. Sheeeeesh. Again thanks for all your help.

[JBH1989]

That really sucks. It seems strange that the airbag light wasn't on if the clock spring was destroyed.

When replacing the steering rack, you lock the steering wheel so it doesn't turn. Once the rack is off, the steering wheel can spin (if not locked) and won't stop so you can easily destroy the clock spring. The clock spring has a bunch of wires and allows the wheel to rotate and carry current for the airbag/horn/steering wheel controls etc. It only allows a certain amount of rotation in each direction. If the rack was installed with the steering wheel 360* out (which is sure what it sounds like) then you have a ton of movement one way and only 180* another way left in the clock spring, and boom, it's destroyed.

I'd go to your mechanic. He HAS to pay for the cost of fixing it. HE SCREWED UP by not following standard procedure (it's not a special Toyota thing, you do it with any vehicle).

[toyseqdrvr]

Hi again, My new indie mech replaced the steering angle sensor and guess what? The VSC lights did not go out. New codes say that the translate ECU needs to be replaced. Funnier than that, I had the ECU replaced three years ago, while under warranty, thankfully. My guy is rattling the cage at Toyota for a free ECU in the meantime. My question is, if you have not already anticipated it, would the faulty ECU computer give an error code on the steering angle sensor and is there a way to bench test it?
Again, Many thanks for all your help.