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Inductive and Hall Effect RPM Sensors

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Inductive and Hall Effect RPM Sensors Explained

Figure 1. RPM Sensors

RPM sensors in today’s vehicles, mainly are using for measuring the rpm and determining the position of crankshaft or camshaft at engine management systems, as well as measuring the speed (rpm) of the wheels at ABS systems, ESP systems, etc. The RPM sensors typically can be Hall or inductive type. The operation of these sensors is fundamentally similar in all instances, although the construction can vary depending on the type of sensor, its intended use or manufacturer application.

Inductive Sensor – Operating Principles and Specification

The inductive sensor, also known as magnetic pickup sensor, during the operational work, as result of inductive effect, in the sensor’s coil is producing the oscillating voltage, i.e. one kind of sinusoidal waveform signal (∼ AC voltage).

When the trigger wheel with the teeth passes in enough close distance (G) to the pole pin of the sensor, the magnetic field surrounding the coil is changed. As the result of the magnetic field changes, in the coil a voltage is induced, which is proportional to the strength and rate of change of the magnetic field. One complete oscillation is produced for each tooth that passes beside to the sensor pole pin. The basic integral components and the shape of the generated signal is shown in the figure 2.

Figure 2. Inductive sensor

Figure 2. Inductive sensor:

1. Sensor housing
2. Output signal wires
3. Coaxial coated protection
4. Permanent magnet
5. Inductive coil
6. Pole pin
7. Trigger wheel
G. Air gap

Depending upon the manufacturer application and type of the sensor, the electrical resistance of the coil is typically in the range between 500 ohms and 1.500 ohms. In some extreme cases, the lowest value can be about 200 ohms, as well as in some cases, the highest value can be up to 2.500 ohms.

The voltage signal produced by the sensor depends on the speed of the trigger wheel and the number of turns in the coil, so an output voltage could be expected between 1 V and 2 V during the engine cranking for example, but in cases at higher rpm, can expected more. The output voltage signal produced by the sensor is weak, i.e. low energy level, so could easily be degraded by other external stronger signals, such as the ignition system for example. For that reason, to eliminate the external influences, the signal wires from the sensor to the control unit are usually shielded with a coaxial coated wires type of protection.

Hall Effect Sensor – Operating Principles and Specification

Unlike inductive sensors, the output signal from a Hall effect sensor is not effected by the rate of change of the magnetic field. The produced output voltage typically is in the range of milli volts (mV) and is additionally amplified by integrated electronics, fitted inside of the sensor housing. On the figure 3 is shown typical build of a Hall Effect sensor. The final output voltage signal usually is in digital waveform pulses (square form). Depending upon the internal electronics of the sensor, the output signal of the sensor can be either positive or negative with peak voltage usually up to 5 V depending upon the type of the integrated electronics and requirements of the used system. The amplitude of the output signal remains constant, only the frequency increases proportionally with rpm. Unlike inductive sensors which generate a voltage signal by itself, the Hall Effect sensors must be additionally supplied by external voltage needed for integrated electronics. The usual supplying voltage (+Vcc) is mainly 5 V but in some cases can be 12 V.

Figure 3. Hall effect sensor

 

Figure 3. Hall Effect sensor:

1. Sensor housing
2. Output wires (+Vcc, −Vcc and signal)
3. Integrated electronics
4. Permanent magnet
5. Hall Effect device
6. Trigger wheel
G. Air gap

 

Diagnostics and Testing Procedures

[Read more…]

Tire Vibration Shortly After Tires are Mounted

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(Tire Sliding on Wheel) Models: 2013 and Prior GM Passenger Cars and Trucks

Information:

Vibration Caused by Wheel Slip
A customer concern of  tire vibration shortly after having a tire or tires mounted may be caused by slippage of the tires on the wheels, placing the imbalance point of the tire away from the weight location. Wheel slip is a condition that occurs when the tire slips and rotates on the wheel during acceleration or braking. This can cause the assembly to become imbalanced and result in the customer returning with a vibration from the tire wheel assembly. Wheel slip is most common on clear coated or chrome wheels with very smooth bead seat areas, but may also occur on other alloy or steel wheels. Most slippage occurs immediately after mounting. Using preferred tire mounting lubricants and proper lubricant application techniques can prevent wheel slip from occurring.

Wheel slip normally occurs for the following reasons:
– Excessive amount of lubricant used or lubricant applied in the wrong locations.
– Improper lubricants. non-preferred lubricants or improperly dilute d lubricants may contain excessive moisture or components that do not dry sufficiently, resulting in an interface between the tire and rim that is excessively slippery.

Checking For Wheel Slip
Vehicles that return immediately with ride disturbances and out of balance assemblies should be checked for wheel slip. Wheel slip can be checked by placing a temporary mark on the tire at the valve stem. After driving the vehicle, if the wheel slip is less than one inch, then wheel slip is probably not contributing to a ride disturbance. When wheel slip is greater than one inch, and you felt a ride disturbance on the test drive, then wheel slip may be causing the vibration.

Note
This diagnostic test will only be effective if the vehicle has been serviced within the last couple of hours.

Vibration after Tire Balance

Best Practices to Eliminate Wheel Slip
Wheel slip can usually be prevented with the proper application of tire mounting lubricants in a controlled and consistent manner. The following are some recommended best practices for eliminating wheel slip.

  1. Prior to the tire installation, clean the tire changer’s wheel-contact parts of any excess lubrication, dirt or grime.
  2. Clean the bead seat areas of the wheel of any leftover lubricant used to demount the tire.
  3. Inspect the tire to be installed and clean any manufacturing related lubricants from the bead area as necessary. Use an approved rubber cleaning fluid that would commonly be used during the tire repair process.
  4. Do not use products containing silicone, alcohol, petroleum based products, solvents or corrosives for cleaning or lubrication.
  5. Lubricate the tire and wheel as shown in the following illustrations. To eliminate wheel slip, the tire beads should normally only be lubricated from “heel to toe.”
    Lubricant applied outside the heel to toe zone will cause the tire to have reduced grip on the wheel and increase the likelihood of slippage. When lubricating the wheel lubricate the safety humps, leave the rim flanges dry and lubricate the drop center area only for difficult to mount tires.
  6. When additional lubrication is required during mounting to prevent tire damage, the excess lubricant should be wiped or cleaned from the tire bead area and the wheel bead seat area before inflating to seat the beads.
  7. The mounting process must be completed within 10 minutes of the application of the mounting lubricant. Evaporation of the mounting lubricant after 10 minutes may prevent proper bead seating.
  8. Inflate the tires to 275 k Pa (40 psi) when mounting, then reduce the air pressure to
    the desired operating pressure.
  9. Place a temporary mark on the sidewall of the tire at the valve stem.
  10. Re-balance the tires and mount on the vehicle.
  11. Park the vehicle for one hour to allow the lubricant to evaporate.

Note: Technicians should not brake or accelerate quickly when moving vehicles from the hoist to the parking lot.

  1. Test drive the vehicle to confirm the ride disturbance has been corrected. Confirm that the mark on the tire is still aligned with the valve stem locations and remove the temporary mark. The above photo shows the possible amount of slip.

Preferred Lubricant Recommendations
To minimize rim slip, always use commercially available lubricants made for bead seating to assist in tire mounting. Paste type lubes are recommended because the application can be better controlled and paste type lubes will not drip onto areas that should not be lubricated. If lubricants that require dilution are used, be sure to carefully follow the lubricant manufacturer’s instructions. Under diluted mixtures will not dry soon enough, which may cause wheel slip. Over diluted mixtures will dry too fast and may hamper proper
bead seating.

Suitable paste lubricants include  Rema Tip-Top(R) Tire Universal Mounting Paste if available in your area, Kent Xtra-Seal(TM) Euro-Paste Mounting Compound or equivalent. The Kent product is distributed nationally. Contact 1-800-YES-KENT for additional information on this product.

Important
When mounting the tires, rubber lubricant must be used. Also, the vehicle should not be driven aggressively (hard acceleration or braking) for up to 24 hours after tire mounting to allow the lubricant to dry. Failure to do so may cause the tire to slip on the rim. This condition will affect wheel balance, which could result in a vibration.

Tire Lubrication
Lubricate the tire as shown in the following illustration. To eliminate wheel slip, the tire beads should normally only be lubricated from “heel to toe.” Lubricant applied outside the heel to toe zone will cause the tire to have reduced grip on the wheel and increase the likelihood of slippage.

Tire Bead Lubrication

Tire Bead Lubrication

Wheel Lubrication
The following diagram illustrates the recommended lubrication of the wheel to prevent wheel slip. Lubricate the safety humps. Leave the rim flanges dry. Lubricate the drop center area only for difficult to mount tires.

Wheel Lubrication Points

Wheel Lubrication Points

Customer Notice
It is advisable especially for customers who are waiting for their vehicle during servicing be made aware that recently mounted tires should not be driven on in an aggressive manner. It may take up to 24 hours before the lubricant is completely dry and tires achieve maximum adherence to the rims. No matter the style of driving exhibited during the drying period, no air loss, or other detrimental attributes are possible from this condition. Wheel slip relative to the rim is merely a customer dissatisfier due to the potential to induce undesired vibration.

Parts Information

Parts Information

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How to detect if the Cummins ECM has been enabled for high idle

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How to detect if the Cummins ECM has been enabled for high idle?

It not to hard to check to see if you have high idle software present. The only thing you need is a resistor that is 39k ohm or greater up to no more than 100k ohm resistor. The other requirement is to have a cold engine. Engine coolant temperature must be below 140 degree Fahrenheit  for this test to work properly. Just unplug the IAT sensor and take your resistor and fold the legs over and insert into the plug. Make sure to the IAT and the resistor are not touch metal or ground. You could put a fold of tape over the plug and resistor for temporary cover. Now just start your truck and leave it idle don’t touch the throttle, brakes, trans (auto), etc. Leave it alone for up to 5 minutes. Typically 2-3 minutes you should hear the idle ramping up to 1,200 RPM’s. If the resistor is greater than 56K ohms then the 3 cylinder high idle will pop up next after reaching 1,200 RPM’s.

How to detect if the Cummins ECM has been enabled for high idle

Table:

High Idle: Detecting if the ECM has been enabled for high idle

High Idle / MPG Fooler Cubby Hole Installation

High Idle / MPG Fooler Diagnostic  

High Idle / MPG Fooler Overhead Console Installation

High Idle / MPG Fooler where to purchase

2010-2012 ALTIMA Rear End Clunking Knocking On Bumps

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Coil Spring Noise over Bumps

 

2010-2012 ALTIMA COUPE NOISE FROM REAR SUSPENSION OVER BUMPS

 

IF YOU CONFIRM:

There is a noise (clunking, knocking or popping) from the rear suspension area when
going over bumps or on uneven roads. [Read more…]

MAF SENSOR or IGNITION CONTROL MODULE TESTING

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MAF-SENSOR-OR-IGNITION-CONTROL-MODULE-TESTING

MAF SENSOR or IGNITION CONTROL MODULE TESTING

How to test a MAF SENSOR or an IGNITION CONTROL MODULE, you’ll hear plenty of specific articles that will guide you step by step through the test. Whether it’s FORD or a HONDA or any of the GENERAL MOTORS makes, you’ll find them here and others. [Read more…]

Positive Crankcase Ventilation Valve Problems

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Positive Crankcase ventilation valve problems

Positive Crankcase ventilation valve problems, Incorrect PCV valve, Rough Idle, Surging engine, Stalling engine, Sticking throttle plate, Excessive oil consumption, PCV System Functional Tests [Read more…]

AIR CONDITIONING ODOR

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Eliminate A/c odors

AIR CONDITIONING ODOR

 

CONDITION

Some customers may comment about musty odors emitted from the Heating, Ventilation and Air Conditioning (HVAC) system at vehicle start-up in hot: humid conditions.

This condition may be caused by condensate build-up on the evaporator core: which does not evaporate by itself in high humidity conditions. The odor may be the result of microbial growth on the evaporator core. When the blower motor fan is turned on: the microbial growth may release an unpleasant musty odor into the passenger compartment.

There are several other possible sources of a musty odor in a vehicle. A common source is a water leak into the interior of the vehicle or foreign material in the HVAC air distribution system. Follow’ the procedures in SI for identifying and correcting water leaks and air inlet The procedure contained in this bulletin is only applicable if the odor source has been determined to be microbial growth on the evaporator core inside the HVAC module. [Read more…]

Pontiac Torrent Engine Overheating

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ENGINE OVERHEATING
 DEFINITION: The engine temperature lamp comes on and stays on: the temperature gauge shows hot or coolant overflows from the coolant recovery reservoir onto the ground while the engine is running.
Step Action Value(s) Yes No
1

 Check for a loss of coolant. Has there been a loss of coolant?

 –

 Go to Step 2

 Go to Step 3
2

 Refer to Loss of Coolant.
Does the engine still overheat?

 –

 Go to Step 3

 System OK
3

 

 Check for a loss of system pressure. Use the J 24460-01 Cooling System Pressure Tester. See Special Tools.
Has there been a loss of system pressure?

 – Go to Step 4

 Go to Step 5
4

 Correct the system pressure.
Does the engine still overheat?

 – Go to Step 5

 System OK
5

 
  1. Check for low coolant protection.
  2. Make sure that the solution is at the specified temperature.
    Is there low coolant protection?

 -37 C (-34°F)

 Go to Step 6

 Go to Step 7
6

 Correct as necessary. Does the engine still overheat?

 –

 Go to Step 7

 System OK
7
  1. Check the accessory drive belt tension.
  2. Check the tensioner. Refer to Drive Belt Tensioner Diagnosis in Engine Mechanical – 3.4 L.
    Is thetensioner working properly and the tension correct?

 –

 Go to Step 9

 Go to Step 8
8

 Replace the tensioner. Refer to Drive Belt Tensioner Diagnosis in Engine Mechanical – 3.4 L.
Does the engine still overheat?

 –

 Go to Step 9

 System OK
9

 Check to see if the timing is retarded by a malfunctioning powertrain control module (PCM).
Is the timing retarded by a malfunctioning PCM?

 –

 Go to Step 10

 Go to Step 11
10

 Correct as necessary. Does the engine still overheat?

 –

 Go to Step 11

 System OK
11

 Check to see if any of the radiator fins are obstructed.
Are any of radiator fins obstructed?

 –

 Go to Step 12

 Go to Step 13
12
  1. Remove or relocate any add-on parts that block air to the radiator.
  2. Remove any debris from the radiator fins.

Does the engine still overheat?

 –

 Go to Step 13

 System OK
13

 Check to see if any of the cooling system passages are blocked by rust or scale.
Are any of the cooling system passages blocked by rust or scale?

 –

 Go to Step 14

 Go to Step 15
14

 

 

 
  1. Drain the cooling system. Refer to Draining and Filling Cooling System (Static Fill) or Draining and
    Filling Cooling System (GE 47716 Fill).
  2. Flush the cooling system. Refer to Coolant System Flushing.
  3. Repair as necessary.

Does the engine still overheat?

 –

 Go to Step 15

 System OK
15

 Check for a pinched or kinked coolant recovery reservoir hose.
Is the surge tank hose pinched orkinked?

 –

 Go to Step 16

 Go to Step 17
16

 Replace or reroute the hose as necessary. Refer to Surge Tank Hose/Pipe Replacement – Inlet.
Does the engine still overheat?

 –

 Go to Step 17

 System OK
17

 Check for an inoperative cooling fan. Refer to Cooling Fan Inoperative in Engine Cooling.
Are there any inoperative cooling fans?

 –

 Go to Step 18

 Go to Step 19
18

 Repair or replace the electric cooling fans as necessary. Refer to Cooling Fan Motor Replacement – Electric.
Does the engine still overheat?

 –

 Go to Step 19

 System OK
19 Check for a loose, damaged, and/or missing deflector.
Are there any loose, damaged, or missingdeflectors?

 –

 Go to Step 20

 Go to Step 21
20

 Replace the deflectors. Does the engine still overheat?

 –

 Go to Step 21

 System OK
21

 Check to see if the thermostat is stuck in the closed position.
Is the thermostat stuck in the closedposition?

 –

 Go to Step 22

 Go to Step 23
22

 Replace the thermostat. Refer to Thermostat Replacement.
Does the engine still overheat?

 –

 Go to Step 23

 System OK
23

 Check for a faulty coolant pump.
Is the coolant pump faulty?

 –

 Go to Step 24

 Go to Step 25
24

 Replace the water pump. Refer to Water Pump Replacement.
Does the engine still overheat?

 –

 Go to Step 25

 System OK
25

 Check for an incorrect radiator.
Is the radiator correct?

 –

 Go to Step 26
26

 Install the correct radiator. Refer to Radiator Replacement.
Does the engine still overheat?

 – _ System OK

Pontiac Torrent Engine Overheating

Tinnerman Nuts Do they need to be Used

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Tinnerman Nuts Do they need to be Used

Tinnerman Nut Do They Need To Be Used

Tinnerman Nut

Tinnerman nut is used to hold the brake rotors in place as it goes down the assembly line. The nuts should never be replaced after the brake rotor is turned, or replaced.  Tinnerman nuts can cause problems on newer vehicles if new  rims are put on the vehicle.Most performance or aftermarket  rims do not have relief cut into the seats to accommodate this thin nut. The driver may report a vibration in the steering wheel or the brake pedal if the Tinnerman nut is left on the vehicle.

Note: If new rims are to be put on your car, or truck, , have the Tire Technician remove the nuts to all four wheels before rims are installed.

 

History:

Tinnerman was founded in Cleveland, Ohio in 1870 by George Tinnerman. It was known as the Tinnerman Stove Company, makers of high-end stoves. In 1936, Albert, George’s son, created a spring steel fastener known as the “Speed Nut®” in order to solve an ongoing issue with stove shipping. From that day, the business expanded in a whole new direction serving multiple industries. George Tinnerman, grandson of the founder, commercialized Speed Nuts in markets beyond stoves – so successful in fact that the stove business shut down entirely. Tinnerman became the supplier of fasteners for 100% of WWII Aircraft.

According to a 1947 Fortune Magazine article, the Tinnerman Company used aggressive techniques to change the automotive industry. The time saving fasteners held parts in place without the need for welding or riveting. At the time, an automobile manufacturer doubted that it was strong enough to hold fenders to bodies. A.H. Tinnerman responded by hoisting a 3,325-pound Plymouth off the ground supported by a Speed Nut. A.H. also created a plan to save Ford millions of dollars by changing the way automobiles are created – finding 400 unique places and application for Tinnerman products. It became an automotive revolution.

By Master Tech Lee