Home > Electrical/Electronics > Safety Audit On Truck Tyres

Safety Audit On Truck Tyres

Safe trucks make for safer roadways—and safe tyres make for safer trucks. In support of National Tyre Safety Week and ahead of next week’s annual maintenance audit of a particular cement company transport department, Automedics offers four key “Pressure Points” as reminders of the importance of proper tire inflation.

The Rubber Manufacturers Association sponsors National Tire Safety Week as part of its year-round efforts to raise awareness of tyre care and maintenance issues.

Safety

Underinflated tyres undergo increased stress and experience higher temperatures, increasing the risk of failure. According to industry research, 90 per cent of tyre blowouts can be attributed to underinflation, and nearly half of all emergency service road calls are tyre-related.

Correctly inflated tyres also help to ensure the best performance of today’s most advanced commercial vehicle safety systems: reduced stopping distance-compliant brakes, full-stability, and collision mitigation systems are all optimised when the vehicle they’re protecting is running on properly maintained tyres.

“Any component that can play a role in the vehicle’s stopping ability can find its performance hindered when tyres aren’t kept at the proper pressure and in good working condition, That’s why it’s so important to catch low-pressure situations quickly and remedy them the same day they are discovered.”

Reflecting the critical nature of tyres pressure to safe operation, underinflated tyres are also a violation in today’s compliance, safety, accountability inspection environment, which can impact a fleet’s CSA scoring.

Tyre temperature

During normal vehicle operation, tyre temperature increases – causing tyre pressure to rise as well. The smartyre pressure monitoring system and smarytre trailer-link for trailer systems both use wheel-mounted sensors to continuously monitor temperature, as well as pressure inside each tyre. These sensors enable the system to provide a deviation value that shows the amount of overinflation or underinflation from the tyre’s cold inflation pressure, automatically taking into account any increase in pressure due to temperature, and adjusting driver alerts accordingly. As a result, these systems can not only address changing situations that can affect pressure – such as whether a truck has been parked for some time or travelled hundreds of miles – but also provide earlier warnings of potential tyre problems.

Cost savings

Because fuel and tyres are typically among fleets’ largest expenses, maintaining the right tyre pressure every day over miles and miles pays dividends in both fuel savings and tread life. Underinflation by as little as 10 per cent can result in a 1.5 per cent drop in fuel economy, according to research by the American Trucking Associations’ Technology and Maintenance Council  and underinflation by 20 percent results in a 30 per cent reduction in tire life.

A TPMS can also address tyre-related downtime costs: The real-time status information these systems provide to drivers or maintenance technicians warns of tyre problems before they pose a safety hazard, and also eliminates the need for manual pressure checks. Tyre inspections and maintenance are made more efficient since terminal operators can tell in advance which tyres may need pressure adjustment.

Big-picture planning

With the right equipment and organisational planning, fleets can sharpen their maintenance team’s scheduling and shape a fleet-wide tyre strategy.

A portal that allows fleet owners to analyse real-time, wirelessly transmitted safety information–connects to systems like smartyre and provides tyre pressures, temperatures, and alerts to the back office. This enables fleet maintenance teams to plan specific vehicle service in advance, while fleet managers can examine and consider factors such as tyre replacement frequency, tyre repair downtime, and occurrences of roadside breakdowns due to tyre failure.

“There’s really no such thing as taking too much care when it comes to a truck’s tyres, so many aspects of safe vehicle operation – and, by extension, highway safety – depend on their maintenance and inspection. That’s why we’ll continue to work on developing and improving ways to keep fleets and drivers running on safe, properly inflated tyres in all situations and conditions.”

READ ALSO  Gene Editing Breakthrough : Scientists Create Programmable Circuits In Human Cells

Generic codes

P1136: Intake valve timing control solenoid valve circuit bank 2

Meaning

The intake valve timing control solenoid valve is activated by ON/OFF pulse duty (ratio) signals from the engine control module. The intake valve timing control solenoid valve changes the oil amount and direction of flow through the intake valve timing control unit or stops oil flow. The longer pulse width advances the valve angle. The shorter pulse width retards the valve angle.

When ON and OFF pulse widths become equal, the solenoid valve stops oil pressure flow to fix the intake valve angle at the control position.

The diagnostic trouble code when an improper voltage is sent to the ECM through the intake valve timing control solenoid valve.

Tech notes

Since the intake valve timing control solenoid valve uses oil flow to control timing, dirty oil can cause the valve to stick open or close. Before replacing the valve, change the engine oil and filter and reset the engine code. If the code comes back you can remove the intake valve timing control solenoid and clean it with brake cleaner.

Possible symptoms

Engine light on (or service engine soon warning light)

Possible engine lack/loss of power

Possible engine rough idle

Possible causes

Faulty intake valve timing control solenoid bank 2

Intake valve timing control solenoid bank 2 harness is open or shorted

Intake valve timing control solenoid bank 2 circuit poor electrical connection

P1137: Lack of heated oxygen sensor switches bank 1 sensor 2 switch indicates lean

Meaning

The heated oxygen sensor 2 (HO2S2) (Downstream), after the three-way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air-fuel mixture (air-fuel ratio) must maintain near the ideal stoichiometric ratio. The HO2S2 output voltage changes suddenly in the vicinity of the stoichiometric ratio. The powertrain control module adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S2 generates a voltage between 0.1 and 0.9 V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The PCM interprets lean when the HO2S2 voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The PCM interprets rich when the HO2S2 voltage is above 0.45 V. The P1137 code will set when the PCM detects that the HO2S2 signal is below the voltage of range for an extended period.

Possible causes

Exhaust gas leaks

Faulty heated oxygen sensor 2 (HO2S2) (Downstream) bank 1

READ ALSO  UK To Develop Electric Car Battery That Can Travel 150 Miles On 6 Minutes Of Charge

Heated oxygen sensor 2 bank 1 harness is open or shorted

Heated oxygen sensor 2 bank 1 circuit poor electrical connection

Inappropriate fuel pressure

Faulty fuel injectors

P1138: Lack of heated oxygen sensor switches bank 1 sensor 2 switch Indicates rich

Meaning

The heated oxygen sensor 2 (HO2S2) (Downstream), after the three-way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air-fuel mixture (air-fuel ratio) must maintain near the ideal stoichiometric ratio. The HO2S2 output voltage changes suddenly in the vicinity of the stoichiometric ratio. The powertrain control module adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S2 generates a voltage between 0.1 and 0.9 V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes lean. The PCM interprets lean when the HO2S2 voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes rich. The PCM interprets rich when the HO2S2 voltage is above 0.45 V. The P1138 code will set when the PCM detects that the HO2S2 signal is above the voltage of range for an extended period.

Possible causes

Exhaust gas leaks

Faulty heated oxygen sensor 2 (HO2S2) (Downstream) Bank 1

Heated oxygen sensor 2 bank 1 harness is open or shorted

Heated oxygen sensor 2 bank 1 circuit poor electrical connection

Inappropriate fuel pressure

Faulty fuel injectors

P1139:  Long-term fuel trim add. Fuel B2 system too rich

Meaning

Long-term fuel trim add. Fuel B2 system too rich is the generic description for the P1139 code, but the manufacturer may have a different description for your model and year vehicle. Currently, we have no further information about the P1139 OBDII code.

Possible causes

Faulty O2 sensor

High fuel pressure

Faulty mass air flow sensor

O2 sensor harness is open or shorted

O2 sensor circuit poor electrical connection

P1140: Intake valve timing control performance bank 1

Meaning

This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake valve.

The engine control module receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant temperature. Then, the ECM sends ON/OFF pulse duty signals to the intake valve timing control solenoid valve depending on driving status. This makes it possible to control the shut/open timing of the intake valve to increase engine torque in low/mid speed range and output in high-speed range.

The intake valve timing control solenoid valve changes the oil amount and direction of flow through the intake valve timing control unit or stops oil flow. The longer pulse width advances valve angle and the shorter pulse width retards valve angle. When ON and OFF pulse widths become equal, the solenoid valve stops oil pressure flow to fix the intake valve angle at the control position.

Possible symptoms

Engine light on (or service engine soon warning light)

Possible engine lack/loss of power

Possible engine rough idle

Possible causes

Faulty intake valve timing control solenoid valve bank 1

Intake valve timing control solenoid valve bank 1 harness is open or shorted

Intake valve timing control solenoid valve bank 1 circuit poor electrical connection

Faulty crankshaft position sensor

Faulty camshaft position sensor

Source: Punch

Leave a Reply

Your email address will not be published. Required fields are marked *