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Veypor VR2 performance computer, troubleshooting speed reading

On my Veypor VR2, it developed a problem where the speed reading would not indicate as it normally did. At first I thought it was sensor at the wheel not picking up the magnet as it rolled past, but as it turned out the problem was in the VR2 unit.

To check if you may be having the same problem as I did, plug in the AC power adapter, and with a DMM, measure the voltage between the two pins at the upper left corner; (looking at the back with the connector at the bottom).
The left pin is ground, and the second pin is the speed sensor input pin.
The voltage should be 5V. If you take a wire and touch it between the two pins, you should see a reading on the speedometer. If you do, then the unit is probably okay, and you'll have to look at the Hall effect speed sensor.

In my case there's a transistor in the unit used to switch the speed signal that started going bad, and the current leakage pulled down the voltage.
After replacing it with another PNP resistor, the voltage at the speed sensor input pin went back up to 5V, and it worked normally again.

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warings lights coming on, SLIP indicator,CHECK indicator, VSC OFF indicator,comes on.


Sounds like a wheel speed sensor may be out of range as far as expected values compared to other wheel speed readings and the VSC goes off because it cannot work with unexpected data values coming into the VSC module. There may be a false high speed reading on one or more of the wheels.

Nov 04, 2011 | 2008 Lexus SC 430

2 Answers

ABS Fault indicator ? Is this an issue or just another money scheme ? Brakes seem to be working fine, truck has 155K on her.


The way the Brakes work on your Colorado, if there is an issue with your ABS, the brakes will still work. You may just not the have ABS brakes active. Most common cause of the ABS indicator is a faulty sensor to one of the 4 wheel. the common ones are the front wheels. Inspect the ABS sensor lead wire which should be along the A-arms to the ABS sensor on the inside wheel hub. Spray brake parts cleaner to the sensor and speed ring to ensure there clean and free of dirt that may be hindering the sensor to read the speed ring on the hub. Look at the condition of the lead wire and inspect for corrosion or any other type of damage. Most of the time a good spray of Brake parts cleaner will fix the problem. If there is an Auto Zone around your area, buy the brake parts cleaner there and have them scan the truck for the DTC codes which would indicate that it is the ABS sensor and not the ABS module, which will be costly and your most likely run it the way it is without ABS due to cost of replacing the module. Good luck friend.

Oct 28, 2009 | 2005 Chevrolet Colorado

1 Answer

brake indicator lamb


My Chiltons manual for the toyota seinna 1998-2002 it says that with the lite always on means ecu malfunction and the action to take is ' ecu problem '. Sometimes these manuals leave a lot to be desired.

there appears to be a speed sensor on every wheel with the abs actuator assembly(including ecu) is attached to the brake booster.

the manual says. . . .The ABS computer(ECU) is mounted within the ABS actuator and is the ' brain' for the ABS system. The function of the computer is to accept and process information recieved from the wheel speed sensors to control the hydraulic line pressure, avoiding wheel lock up. The computer aslo constantly monitores the system, even under normal driving conditions, to find faults within the system.
If a problem develops within the system, an "ABS" light will glow on the dashboard. A diagnostic cod will also be stored in the computer and, when retrieved, will indicate problem area or component.

I hope this helps

Aug 10, 2009 | 2002 Toyota Sienna

1 Answer

ABS brake module sounds like a motor running and won't stop unless battery is disconnected. what is fix?


I would pull the fuse for the ABS hydraulic pump and then put it back in and see what happens. Don't ever recall a pump running. Dealer may need to hook up scan tool for diagnostic fault codes, DTCs.



Principles of Operation
The ABS control module receives wheel speed readings from both front wheel speed sensors and the rear differential speed sensor, and processes this information to determine if an ABS event is necessary. The wheel speed sensor electrically senses each tooth of the ABS sensor indicators as it passes through the wheel speed sensor's magnetic field.
The ABS control module continuously monitors and compares the rotational speed of each wheel speed sensor indicator and, when it detects an impending wheel lock, modulates brake pressure to the appropriate brake caliper(s). This is accomplished by triggering the hydraulic control unit (HCU) to open and close the appropriate solenoid valves. Once the affected wheel returns to normal speed, the ABS control module returns the solenoid valves to their normal position, and normal (base) braking resumes.
The ABS control module is self-monitoring. When the ignition switch is turned to the RUN position, the ABS control module will do a preliminary electrical check, and at approximately 20 km/h (12 mph), the pump motor is turned on for approximately one-half second. Any malfunction of the ABS system will cause the ABS to shut off; normal power assisted braking, however, remains.
Inspection and Verification — Scan Tool Communications Check
  1. Verify the customer concern by carrying out the Drive Cycle Test.
  1. Visually inspect for obvious signs of mechanical and electrical damage.


Visual Inspection Chart Mechanical Electrical
  • Parking brake cable
  • Tire pressure
  • Tire size or mismatched tires
  • Blown fuse
  • Central junction box (CJB):
    • fuse 23 (10A)
  • Battery junction box
    • fuse 102 (50A)
  • Connectors or connections
  • Ground integrity
  • Harness routing
  • Wire chafing
  • Circuitry open/shorted

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Anti-Lock Control The four-wheel anti-lock brake system (4WABS) consists of the following components:
  • Anti-lock brake control module (2C265)
  • Front anti-lock brake sensor (2C204)
  • Front anti-lock brake sensor indicator (2C182)
  • Hydraulic control unit (2C219)
  • Rear anti-lock brake sensor (2C190)
  • Rear anti-lock brake sensor indicator (2C189)
  • Yellow ABS warning indicator

May 07, 2009 | 2000 Ford Expedition

1 Answer

Problem with my cruise control and ABS light on 03 Explorer


Anti-Lock Control —Vehicles Built After 03/2002 The 3-channel anti-lock brake system consists of the following components:
  • front wheel speed sensors
  • front wheel speed sensor rings
  • hydraulic control unit (HCU)
  • Anti-lock brake control module (ECU)
  • rear wheel speed sensor
  • rear wheel speed sensor rings
  • yellow anti-lock brake warning indicator
The 4-channel anti-lock brake system with traction control and stability assist system consists of the following components:
  • active brake booster with integral solenoid
  • brake booster release switch
  • front wheel speed sensors
  • front wheel speed sensor rings
  • hydraulic control unit (HCU)
  • stability assist module (ECU)
  • stability assist event indicator
  • lateral accelerometer
  • longitudinal accelerometer (4x4)
  • rear wheel speed sensors
  • rear wheel speed sensor rings
  • steering wheel position sensor
  • yaw rate sensor
  • yellow anti-lock brake warning indicator
  • brake pressure transducer
  • traction control switch
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I suspect the abs issue is causing the speed control not to work if it happened at the same time the cruise control stopped working. When the yellow ABS light comes on, it means the ABS is dactivated. You may have a faulty accelerometer which senses acceleration and yaw (side to side lean). I have not seen a bad one but you said it is sensitive to acceleration.
I would unplug it and see what happens. The connector should have a small tab to depress so you can pull the connector out.
Here is where it is:

Accelerometer Removal and Installation
  1. NOTE: The accelerometer is located under the center, rear passenger seat carpet. (I think you have to remove seat for access).
    Cut the carpeting along the perforations.
  1. Disconnect the electrical connector.
  1. Remove the nuts and remove the accelerometer.
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Have dealer hook up tester and pull fault codes if you can't find an easy solution.
Some background info
  • A malfunction in the anti-lock brake system will cause the anti-lock brake control module to shut off or inhibit the system. However, normal power-assisted braking remains.
  • Malfunctions are indicated by the yellow ABS warning indicator in the instrument cluster.
  • The anti-lock brake system is self-monitoring. When the ignition switch is turned to the RUN position, the anti-lock brake control module will carry out a preliminary self-check on the anti-lock electrical system indicated by a three-second illumination of the yellow ABS warning indicator in the instrument cluster.
  • During vehicle operation, including normal and anti-lock braking, the anti-lock brake control module monitors all electrical anti-lock functions and some hydraulic operations.
  • Each time the vehicle is driven, as soon as vehicle speed reaches approximately 20 km/h (12mph), the anti-lock brake control module turns on the pump motor for approximately one-half second. At this time, a mechanical noise may be heard. This is a normal function of the self-check by the anti-lock brake control module.
  • Pedal pulsation coupled with noise while braking on loose gravel, bumps, wet or snowy roads is normal and indicates correct functioning of the anti-lock brake system.
  • Warning Lamp Indicator
    The anti-lock brake system (ABS) uses the yellow ABS warning indicator to alert the driver of a malfunctions in the ABS.
    The yellow ABS warning indicator will come on to warn the driver that the ABS has been turned off due to a symptom that exists in the ABS. Normal power assist braking remains but wheels can lock during a panic stop while the yellow ABS warning indicator is illuminated.

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    Please report back, I am curious if that is what it is. Good luck

    Mar 03, 2009 | 2003 Ford Explorer

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