Peak code: 0F-8C Map controlled thermostat circuit/control

[swb03]

Most of the posts I saw point to the thermostat. Does that sound accurate?

If it is the thermostat, does that mean I should replace the water pump at the same time?

Any help is appreciated,
Sean

[Edwin NL]

It's the sensor on top of your Tstat/waterpump

[spazzboy]

I have the same code. I am replacing the thermostat only.
Edwin, please tell me this is correct and I don't have to purchase a supplementary sensor.

[reddd]

In my case the connector was melted to the thermostat and the wiring was burned back about 3 inches. After repairing the wiring and connector I did not reconnect the wiring and run the car with the mechanical thermostat only. It doesn't throw a CEL but does give a peak fault code.

[Edwin NL]

I have the same code. I am replacing the thermostat only.
Edwin, please tell me this is correct and I don't have to purchase a supplementary sensor.

Sensor should come with it.

My car has had the code for 2 years now it's only for the cold start to reduce the CO2 emissions.

I can replace it but it will crap out in a year again.

[swb03]

Spazzboy - curious why you are replacing the whole thermostat?

I read a few posts saying I can swap out the sensor without draining the coolant (a little will leak). Any issues with that?

Thanks for the replies.

[spazzboy]

Spazzboy - curious why you are replacing the whole thermostat?

I read a few posts saying I can swap out the sensor without draining the coolant (a little will leak). Any issues with that?

Thanks for the replies.

The idea was preventative maintenance. Now I am wondering if I should even bother if it not a critical error message.

[swb03]

As if I didn't have enough problems, I got the dreaded trans failsafe error message today...

On my way home from work, some clown in an older Mustang was egging me on and like an idiot I took him up on it. Started off of a red light at a pretty good clip and then both of us punched it. I had him until I heard a thud along with a loss of power, the trans failsafe error on my cluster, speedo gone and the abs/dsc on. I immediately had my foot off the gas and got into the right lane taking it slow. Funny thing is, it seemed fine. By that I mean I didn't experience any of that stuck in 3rd or 4th gear thing that I've seen posted. It actually shifted fine up through the gears after a complete stop and the error message went away about 30 seconds after it appeared. However, the battery warning light soon took its place on my cluster.

My question is: can what I'm describing above possibly be related to the thermostat / sensor? Everything I'm reading points to my alternator (recently got a new battery), but the timing of these events has me wondering...

Any input would be appreciated.

[IcemanBHE]

No. Not related. I also have this MAP code....and have for about 2 years.

Edwin and I discussed this last night....He thinks this MAP code is due to the fact that the temp is reported to the DME and only matters on cold starts. Pretty small detail.

Here is a INPA screen of this same code on my car.

http://i795.photobucket.com/albums/yy233/IcemanBHE/Diagnostics/DMEErrorList.jpg



I would check your belts and alternator. I assume it drove OK so you didnt lose your PSP belt.

[swb03]

Thanks Iceman.

Just checked my voltage with the car off: 12.4. That doesn't seem bad to me - at least not enough to cause the battery warning light.

[IcemanBHE]

12.4 is the dead minimum BEFORE goofy things start to happen.

Q has a sheet he can share, but IIRC 12.4 is like 75% charge remaining on the battery.

BTW..that same test performed when running should yield 13+VDc

If not...dead alternator.

[swb03]

12.4 is the dead minimum BEFORE goofy things start to happen.

Q has a sheet he can share, but IIRC 12.4 is like 75% charge remaining on the battery.

BTW..that same test performed when running should yield 13+VDc

If not...dead alternator.

You're right, when I started trickle charging the battery it said I was only at 63%... Ouch. Almost done charging now and will see what happens.

Thanks again for your help.

Battery completely charged and I still have the red battery light on my cluster. Also took it around the block and the transmission is shifting like crap. Seems crazy to me that an alternator can cause issues like this.

[IcemanBHE]

Welcome to the E38. :)

[kimokk]

It's the sensor on top of your Tstat/waterpump


Can the sensor be replaced by itself or do you have to buy the whole thermostat housing?