Diagnose yourself!

Who hasn't experienced the yellow engine light in the instrument panel? Is it something serious, or can it wait? Why can't I reset the code myself?

 

The instruction book says that you must visit a workshop as soon as possible, without telling what is wrong. You get an appointment on Monday and postpone the planned trip to the cabin while waiting for what the workshop people have to say. Then it turns out that there were no mistakes - nothing. The error code is reset at the workshop and you will receive a bill of NOK 1 or thereabouts.
 
Without it being scientifically proven, I think the check engine lights most often light up on models between 2001 and 2010. We bought 5 new cars during this period, and the yellow check engine lights came on at us occasionally and often. On one occasion it was a legitimate fault (air flow meter), otherwise it was a false alarm.

What happened in 2001?

It actually began in 1996 when the US authorities required that all new cars manufactured in the US should be equipped with "On-board Diagnostics" as specified in OBD-II. This affected not only GM, Ford and Chrysler, but also Mercedes, Honda and Toyota with their own production facilities in the USA. Five years later, in 2001, the EU introduced a corresponding European requirement called EOBD (European OBD). If you own an American-made car from 1996 or a European car from 2001, you can be one hundred percent sure that it complies with OBD-II/EOBD. It is true that some cars received OBD before the regulations were introduced, but they are exceptions.
 
OBD-II/EOBD was mainly pushed to ensure that cars' exhaust gas cleaning systems work properly. In the event of a fault, the car ends up in a workshop, where the mechanic must be able to see what is wrong by plugging in a fault code reader. Everything must be standard. There are requirements for how the contact should be designed, where it should be located, which protocol should be used, and which codes should be used. The system should not only give the mechanic the opportunity to read stored fault codes, but also run self-tests on important exhaust gas functions.
 

If you have an OBD-II/EOBD car, you can buy your own error code reader at Biltema for NOK 469, find the special trapezoidal diagnosis connector and run a diagnosis without getting your hands dirty. All the connectors I have seen are to the left of the steering wheel, at the bottom under the dashboard. It is actually a requirement that the socket be located no more than 3 feet from the driver's seat.
 

I tested the fault code reader on our Honda Civic 6 manufactured in Canada between 1996 and 2000, with OBD-II of course. The innards in the catalytic converter have started to rattle without the engine light being on. As expected, the trouble code reader didn't show any errors either. I observed that the error code reader found the correct protocol, ISO 9141, and queried the system. Via the Biltema reader, you can run separate "selftests" for, among other things, the catalytic converter and lambda probes. These too returned zero errors. When I tried the pre-heating system for lambda probes and catalytic converter respectively, I was told that this did not exist - quite correctly. Thus, I think that it is not so dangerous if the youngest man in the house is allowed to drive with a rattled catalytic converter until Christmas.

A simple error code reader - similar to the one you can buy at Biltema - is good enough for most of us. They give you the opportunity to make a decision, for example, whether you can continue to drive for the next few days and weeks, whether you can - or want to - change yourself, or can just reset the code and drive on to see if it comes back. All this costs far less than a visit to the workshop. And the best of all is that if you can drive a car, you can operate a completely "basic" hand-held error code reader.
 
Biltema sells three simple car testers, one so-called generic which is suitable for Chrysler and Toyota, among other things - another is adapted to cars from the Volkswagen group, while the third is adapted to Volvo. What the devices have in common is that they only give you the codes - not in plain text. So you have to find out what the codes mean on Google, or use the included mini-CD. If you spend a few hundred bucks, you can have the codes translated into plain text, and I don't see any point in it. I recommend Google, because then you can get advice and tips from other car owners.
 
More expensive testers provide the opportunity to capture several types of faults from subsystems such as airbags, ABS, climate control, transmission systems and so on. You can also get the opportunity to carry out brand-specific "selftests", more options for resetting error codes in the engine and subsystems, as well as carry out detailed measurements that can be useful in connection with fine-tuning and possible trimming of engines. Although more expensive car testers are rarely necessary for most of us, I do not rule out that they can be nice to have. If you have a car, you should wish for an error code reader for Christmas.
 

You never know when the yellow light will come on...

 

 

See

Fault code readers at biltema.no