Essential things vehicle owners should know

By Kunle Shonaike

In a previous article, we mentioned essential things vehicle owners whether new, old or an aspiring owner should know to give proper care for their vehicles and get the best out of them. Knowledge of this can help you to identify a competent technician from a quack waiting to get your money and cause more damages to your vehicle.

We had written about knowing the right engine oil specification for vehicles and also the service interval for engine oil lubricants service. In today’s article, we are revisiting essentials that all vehicle owners must know.

No more engine warm up: Some years back, it was a popular practice to see vehicle owners start the vehicle in the morning and make it run for several minutes before setting out on the road for the day. This however has been phased out due to advancement in technology and the increase in electronics on vehicles. Vehicle computers get information from the monitors(sensors) to know what is happening around the engine, and know how best to control the situation to bring about the best performance from the engine. Warming up of the engine will only amount to a waste of fuel, increase in emission and could also shorten the engine life.

Don’t remove the thermostat: This would surprise long-time vehicle owners as I am sure a piece of advice they got when they bought their cars is to always remove the thermostat from the engine. The excuse is that the thermostat is used because of the cold weather conditions where such a vehicle comes from. Anytime I hear such myths about thermostat, these two questions come to my mind and when I ask for an explanation without any tangible reply.

Do vehicle manufacturers produce just to be used in their region?

Most of the places referred to have winter and summer seasons. During summer, some of these places are hotter than our weather. Does it mean they remove the thermostat from the engine at this time?

Thermostat is one of the devices that make the engine get to its operating temperature as fast as possible and this helps to reduce fuel consumption.

Thermostat if removed from the engine causes the engine to take longer time to warm up and attain its optimum operating temperature. The longer this takes, the more the fuel that would be burned. It also affects the health and life span of the engine.

This piece is written by my mentee Ibrahim Ogundele.

Generic codes

(1) P0946: Hydraulic pump relay circuit range/performance

Meaning

The transmission control module monitors the hydraulic pump relay. The TCM sets the OBDII code when the hydraulic pump relay is not to factory specifications.

Possible causes

Faulty hydraulic pump relay

Hydraulic pump relay harness is open or shorted

Hydraulic pump relay circuit poor electrical connection

(2)P0947 Hydraulic pump relay circuit low

Meaning

The Transmission control module monitors the hydraulic pump relay. The TCM sets the OBDII code when the hydraulic pump relay is not to factory specifications.

Possible causes

Faulty hydraulic pump relay

Hydraulic pump relay harness is open or shorted

Hydraulic pump relay circuit poor electrical connection

(3)P0948: Hydraulic pump relay circuit high

Meaning

The transmission control module monitors the Hydraulic pump relay. The TCM sets the OBDII code when the hydraulic pump relay is not to factory specifications.

Possible causes

Faulty hydraulic pump relay

Hydraulic pump relay harness is open or shorted

Hydraulic pump relay circuit poor electrical connection

(4)P0949: Auto shift manual adaptive learning not complete

Meaning

The transmission control module monitors the auto shift manual signal from the auto shift manual switch. The TCM sets the OBDII code when the signal from the auto shift manual switch is not to factory specifications.

Possible causes

Faulty auto shift manual switch

Auto shift manual switch harness is open or shorted