Car Repair Diagnosis

Car Repair Diagnosis – The Computer Does Not Make it Simple!

Today we’re going to do a diagnosis on an Acura 3.2 TL. Our clients complaint is that the check engine light is on and the vehicle otherwise runs fine.

We’re going to go through the whole diagnostic process and you’re going to get to see just what’s involved in diagnosing a “check engine lamp” concern.

Clients often are concerned about the cost of diagnosis. They can’t quite understand what’s involved.

“Can’t you plug a computer in and tell me what’s wrong with it?”

Auto Repair Diagnosis Our clients complaint is that the check engine light is on and the vehicle otherwise runs fine.

We’re going to go through the whole diagnostic process and you’re going to get to see just what’s involved in diagnosing a “check engine lamp” concern.

Clients often are concerned about the cost of diagnosis. They can’t quite understand what’s involved.

“Can’t you plug a computer in and tell me what’s wrong with it?”

Diagnosis for Check Engine LampOnce we plug it in… that only gives us a direction with the information. To find out what’s wrong we have to follow up with further tests. The piece of equipment that we’re going to use today is our Snap-On Modus diagnostic tool.

We can scan the vehicle’s computer and from there we can get the basic information about what codes are stored in the vehicle’s computer.

On our scan tool, we’ve got several codes that are stored. One, the P1676 I’m not certain of so we’ll have to look that one up. There’s several engine misfire codes from cylinders 1, 4, 5, 6 and there’s also a code for the Evap system.

Diagnosis Computer CodesWe’re going to take the vehicle on a road test now to find out what’s going on… I’ve been driving for a little bit and the engine doesn’t appear to be misfiring and it seems to be OK.

Back at the shop, let’s look into those trouble codes that were shown on the scan tool in 3 different systems of the vehicle. The first issue P1676, is a communication issue between the transmission computer and the vehicle computer.

The second issue is all the engine misfire codes. The third issue is the P1456 Evap code and that seems to be involved with the fuel cap. That has been a very common failure on this vehicle.

We produced this video to show you what’s involved in diagnosing a modern vehicle that has the check engine lamp on. The test procedures are different for every vehicle and every type of concern.

The basic principle is still the same. It is not simply a matter of plugging in the diagnostic computer and having it tell us what is wrong. The computer is only part of the diagnostic process, giving us trouble codes and information that the vehicle computer sees.

Diagnosis Ignition coil replacementFrom here, we must test specific components and wiring circuits to find the real cause of the concern. During this diagnosis you got to see both a simple and a complex diagnosis and we hope that this helps you understand what’s involved in properly diagnosing and repairing a modern vehicle.