I am getting the Low Coolant message so I hooked up my Ultra Gauge to monitor coolant temp. I was running errands when I got a transmission fault message. Immediately went drove home and pulled the following codes
P0302 misfire A2
P1313 misfire rate Catalyst damage fault Bank 1
Pending codes:
P1316 Injector Circuit/IDM codes detected
P1797 ?
I think I can take care of the misfire codes, but I am concerned about the P1797 code.
Any thoughts?

 

P1797 - CAN ECM token message missing

Hmmm...others will weigh in, but this might be just a glitch. You might consider unplugging, cleaning and reconnecting the TCM from its harness.

Sounds like you have a number of things happening at once...if this is the first glitch you've gotten from the gearbox in a while, you might be fine there with a simple clean and reconnect.

Good luck with all of it.

 

+1 to The Coupe. Both replying at the same time.

That's some combination. Low coolant and misfire sort of go together but then to get a transmission fault..............

The pending P1797 transmission DTC is : CAN ECM token message missing

Possible causes are listed as:
Other CAN control module fault
CAN open circuit - ECM to TCM
CAN short circuit fault
ECM failure
TCM failure

You wouldn't have been able to drive home with either ECM or TCM failure and it's highly likely a short or open circuit would also have brought you to a halt. That leaves 'other CAN control module fault' as the reason for the code. Not very informative!

Now you know the stored and pending codes, I'd be considering clearing them and watching for a repeat.

Graham

 

It's seems like mine P1638, the car dead in road suddenly

 

Do I need to disconnect the battery to clean the TCM connector? If I understand correctly, disconnecting the battery will clear the codes.

Thanks

 

Ignition off is OK for cleaning the connector. Disconnecting the battery will not clear the codes - you'll need a scantool to clear them.

Graham

 

P1797 was my biggest problem. Autoengiuity identified as a communication malfuntion between TCM and ECM. But I also at times had P1898- TCM/ Instrument pack malfunction. After clearing it took 5- 15 min. to recur. I finally got rid of it by replacing the TCM. I get the feeling the ECM was being confused by a ABS module problem combinesd with the TCM problem and throwing the towel in. However, I do not have enough running time since the replacement to be certain my problems are over.
'97 XK8 Aquamarine 85K mi.

 

please follow up RJ237 after some time, it would be great to hear if it comes back. Thanks!

 

I was out shopping this morning and decided to get on the interstate and check on what I thought was a balance vibration when I brought the car home from the dealer (it was).
I had not been using the Ultragauge for local driving, but wanted to see what the temp. was at 75- 80 mph. When the Ultragauge came online it began signalling impending trouble code and then the car displayed gearbox fault, but didn't go into limp mode.
I stopped, turned the engine off, and disconnected the Ultragauge. No codes or faults on restart, and drove for another 20 min. with no problems.
I have now cleared the codes, including P 1797 and P 1798, and will begin a series of trials, with and without Ultragauge. The scientist in me is suspicious. I am not sure if I ever had the fault happen without the Ultrgauge, but I don't think so.
This will take a few days as I want to finish painting my house while we have some cool weather here in Douglasville, but I will be back with results.
RJ
________________________________________
'97 XK8 Aquamarine/ Cashmere 85K mi.

 

RJ237,
When I got the P1797, I was using the Ultra Gauge. I hooked up an Innova 3130 , no P1797! I am suspicious now too of the Ultra Gauge.

I had oil in the #2 spark plug hole. Cleaned it out as best I could and cleaned the plug. Cleaned the TCM connection. Cleared the codes(P0302,1313,1316) with Ultra Gauge. I will take it for a spin on the same route that I got the codes and see what happens.

 

I know there are other XK8 owners using the Ultragauge, but so far no reports of problems. I am going to drive a total of about 100 mi. and check for codes with Autoenginuity each time I get home. Then I'll start using the Ultragauge and see what happens. I find it hard to believe the Ultragauge is storing old codes without displaying them with the engine not running, but there was nothing on mine when I checked today.

 

No codes after driving about 8 city miles. Maybe just a glitch on the P1797?
I have ordered a coolant level sensor. That should get rid of the low coolant message.

 

my guess is communication error with the ultragauge. Only use it after you get a fault, or only when you need to monitor real time data, i.e. fuel trims, etc.