Hello everyone I have a 02 xtype 2.5 I recently got a check engine light and not sure what these codes mean through the diagnostic trip trick. I have codes E510, D900, A979, 9318 and 9359 if you could please help me out to find out what these mean.

 

XJag02, here is what you have:

E510 = U2510: PATS-ECM mismatch. This is caused if you replace the ECM or the PATS module (aka, remote keyfob access computer) and now the numbers inside the computers do not match up with what they are expecting from the other computer. This will cause the car to think that it is being stolen and will cause the car not to start. This is one of those codes that I see a lot with no problems noted. I believe this to happen when the computers attempt to transmit the data and the data gets corrupted once. But, on the second start, all is good. But, the code will still be locked into the car.

D900 = U1900: Dynamic stability control fault caused by a CAN bus system failure. This is common to almost every car that I see. So, unless you are having a CAN bus issue right now, I would ignore this code.

A979 = B2979: Not sure what this one is as my DTC summaries don't cover anything with that high of a number. Doing a little bit of research and finding something about a Mazda (shares a lot of the same code logic as the Jag), this relates back to the A/C compressor reaching the high pressure cutout. This can be caused by the engine fans failing to kick on at the correct times or a problem with a blockage in the A/C system. This is one of those things that unless you are familiar with freon systems, this is best left to a professional due to environmental laws.

9318 = B1318: Automatic headlight leveling system seeing a voltage outside the 9-16V range. Odds are, you had a battery run low or you turned on the car at some point with the battery disconnected and the computer had just a little bit of power left in it for it to see the condition and set the code. I would not worry about this at the moment.

9359 = B1359: Ignition switch voltage problem. This will occur if the computer thinks either the switch voltage source is shorted to ground and/or it has an open in the power wire. Normally this will be characterized with certain items (say the dash blower, the radio, wipers, etc) not working with the car running.

 

None of those seem like the problem I'm having. I have a bit of a ruff idle and car seems to be suckling more gas than usually. Is there a way to clear the codes and start fresh to know which ones are recent?

 

Just get an OBD tool. E.g. elm327 from $5

Cluster codes can be years out of date and not have current ones. Ignore them.

 

XJag02, you can try disconnecting the battery for a few minutes to reset the computer and see if things will clear up (this will force all the codes to clear in the ECU, but the codes in the instrument cluster can only be removed using a factory tool).

I would do a few things before spending lots of time trying to throw parts and major time at the car. First, get yourself a can of "throttlebody cleaner" (not carb cleaner). Remove the intake hose and clean the inside of the throttlebody. If you see brown, wash it away. Make sure to use your finger and manually open up the butterfly valve and clean the inside of that too. Do not forget to clean the edges of the butterfly valve as this can build up gunk on it and cause the butterfly valve to stick and lead to a rough idle.

Next, remove the Mass Air Flow (MAF) sensor. Get a can of MAF Sensor Cleaner and spray that into the sensor. Just don't spray straight down the tube. YOu want to bounce the spray off of the walls. Spray directly down into the sensor can lead to damage of the small wires inside the sensor.

The last thing I would ask is "when was the fuel filter last changed"? If you don't know or it has been more than 15K miles (25000KM), probably time to do that.

If you are still having issues, then I would say you need to start looking at the coils and/or the spark plugs. It is not uncommon as our cars get older to develop an oil leak into one of the plug wells and this will cause a cylinder to misfire, leading to the rough idle. Granted, this will normally throw a code. If you don't have a check engine light, then what I would tell you to try is finding a back country road or a long freeway entrance and do a hard acceleration from stop (or as slow as you can reasonably go based on conditions) to a decent speed 60+ MPH (100+ KPH). This will tend to cause a code if there is a minor problem. That will give you a starting point of what cylinder is giving you trouble. We can then take things from there.

 

On an OBD2 scanner where do you find numbers you need to enter for inputting DTC codes?

Thanks

 

If you are trying to see what codes your car might have, scroll up one position Diagnose function of the reader. That should scan the system and give you a list of any codes that come up.

 

I did try Diagnostics settings; Choosing either Read Codes, or Erase, just came up with message is
car OBD2 compliant

 

I did a quick search and it looks lik ethere are some youtube videos on how that unit works. Didn't it come with a user manual or a link to a website that has a user manual? Usually those things are pretty straightforward to use. When that question comes up if it OBDII compliant isn't there a way to click "yes" or "no"?

 

Is your ignition key off on OBD connection, then turn key to on (not started)?