I had the VDP scanned and came up with the following codes:


P0118 Engine coolant temp sensor
P0125 Ineffecient coolant temp for closed loop fuel control
P0116 Engine coolant temp sensor


P1775 Manufacture specific code


So I am needing a new temp sensor but what is the P1775 code? Its $1000 to get the European update for the scantool.


Can anyone help with the P1775 code.......


Thanks
Andy

 

P1775 TCM CHECK ENGINE MIL request - Possible transmission fault – check for flagged TCM DTCs

That's the description in JTIS. Have you had any other transmission codes? Possibly a stall? I'd expect this one to be associated with another as this appears only to be the Set MIL request. If you don't have any other Trans codes I'd just clear this and see if anything comes back.


For your other codes, check the wiring for the coolant sensor before replacing it.

 

Hi Andy,

According to the X300 Diagnostic Manual, which I believe is available free in the download section of this forum:

P1775: "MIL illumination request from TCM."

MIL=Malfunction Indicator Lamp (U.S. Check Engine Light or Service Engine Soon light), TCM=Transmission Control Module. The manual gives instructions for testing with dealer-level equipment, but also suggests checking the electrical connectors and harness for condition and integrity (presumably the main connector at the TCM and the electrical connector at the transmission). Something else worth checking would be the electrical connector at the Throttle Position Sensor (TPS) on the throttle body. Oil contamination of that connector, or of the TPS itself, is known to cause transmission-related faults. As Brendan suggests, it would be worth just clearing the code and waiting to see if it reappears.

Regarding the three CTS codes (the manual also uses the abbreviation ECT for Engine Coolant Temperature sensor), all three codes together probably do indicate failure of the sensor itself (which is inexpensive if you shop around, and easy to replace), although a possible cause of two of the codes 116 and 125) is a thermostat seized open. Brendan's suggestion to check the wiring harness is a good one, but since 116 and 118 are triggered by opposite malfunctions, 116 by high resistance when hot or intermittent high resistance, 118 by a short to ground or low resistance in the sensor, the only thing I can think of that fits besides a failed sensor would be a broken wire that is intermittently contacting ground. Early XJ40s had an issue with the CTS wiring shorting to the hood/bonnet, but I've never heard of that on an X300.

If you can't find the Diagnostic Manual in the download section of this forum, send me a PM with your email address and I'll send you the pdf file.

Also, search the forum archives for scanners that are known to work with the X300 - I'm sure there are many solutions for far less than $1,000.

Cheers,

Don

 

Check the archives. That code many times simply means the engine and transmission show different speeds for the main shaft, while at speed, which would normally be a fault with the transmission... unless the engine has stalled!

If your drivability symptoms include a rough idle and stalling, you could either have a bad sensor as you have surmised OR your thermostat might be sticking open and not allowing the engine to heat up properly, either one not allowing the engine to go into vclosed loop control.

 

Thank you gents.....


I have the Snap-on Solus Pro scan tool and I have to go into the Global mode to scan the Jag. I couldn't get it to read the P1775 code any further. This is new stuff to me so I'm learning as I go.....


I couldn't get the diagnostic to open up for me.


Don pm sent....

 

I am not familiar with that scanner, but I would think it should read transmission codes. See what the documentation says about reading codes from a different module. The P1775 is just a general code from the OBD system that says the transmission has a fault- implying you should scan the transmission module.

I don't think it matters anyway in this case it is almost surely the mismatched shaft speed error after an engine stall.

You might want to use the scanner to read the engine coolant temperature to see if you can get an idea if the sensor is reading right and the engine is just not hot, or if it seems to be a bad sensor.

 

It seems that my thermostat and temp gauge work as it takes 4-5 minutes for the temp gauge to move up to the normal mark.









I did have a couple stalling issues last winter when I hit deeper snow.




Thanks again for all the help/replies.....

 

You probably know this already but the temp gauge readings displayed on the dashboard and the temp read by the ECM are measured by two different sensors.

So it is quite possible to have the gauge read normal because the temp sender is fine yet the engine thinks otherwise because of the ECT sensor being faulty. Measure the resistance of the sensor as the engine warms up. Here is a graph showing expected values.



If the values are correct, then I would suspect a wiring problem or connection issues at the ECM.

 

Allan I did not know that. I'll have to see if I can find the other sensor....


Thank you for the info....

 

Allan,
Wouldn't an OBDII reader with live-data capability read the value the ECM is seeing? (Just thinking of easy ways to check it - if faulty...then worry about finding it)