More bitchy codes
 

75 Brake-light switch, line
7B Activation, map cooling
78 Plausibility, accelerator and brake pedals
27 Plausibility, signal, brake-light switch/brake-light test switch
28 thermal sensor for oillevel defect

One of these caused the cruise control to disengage and it would not come back, then a few minutes later the BRAKE ABS lights came on along with the triangle/exclamation point.

Brake lights work fine.

Maybe "P1620 Map Cooling Thermostat Control Circuit Signal High" is related to 7B?

Check the brake pedal position sensor wiring and rest position. If needed renew the sensor. Thermostat map cooling is a failed heater coil on thermostat. Renew the thermostat. Oil level sensor problem is more cosmetic. Renew the sensor on the next oil change.

I changed my sensor gasket with full oil using a vacuum cleaner to keep the oil in. It's a very nice hack. I've used a few times now for various things like putting in a drain plug with valve.

Brake pedal sensor feels like your main issue but if you have the right scanner check that both gas pedal pots are reading opposite scales.

Thanks. I didn't even know there was an oil level sensor (other than the dipstick).

I'll check the others. If I don't replace the t-stat will that eventually cause a problem? Because it looks like a pain in the ass considering where it is.

More bitchy codes
 

M54? Tstst is 3/10 difficult one of the easier jobs. Just follow the steps ding try to take a shortcut like leaving fan shroud on (personal experience).

A neat trick i do to reattach the fan is to wrap electrical tape around the nut about six wraps (clockwise while looking at the nut opening) and keep the roll attached as a handle. Pull slowly to turn the nut.

I broke my thermostat by using the hammer on wrench method to loosen the fan while the coolant was under vacuum making the upper hose stiff! So learn from my mistake.

https://uploads.tapatalk-cdn.com/202...7862780fca.jpg

Sender for oil looks like this. Had to change the gasket on mine recently was leaving several oz of oil every day on the ground.

Thanks y'all!

If the oil level sensor is bad, wouldn't it turn on the low oil light? Because it's not nor was it ever on other than for 0.5sec after starting. I might pass on that one.

Is there a drain valve for the coolant or do you yank off the lower hose like a barbarian? That blue shit is expensive and it was replaced when I had the water pump done a few months ago, so I'd like to drain it into a clean container and reuse it.

There is a plastic blue 13mm hex drain plug on the bottom left of the radiator. You can get most of it into a clean bucket.

The oil level sensor if bad should turn the oil light on orange when you first start the car. Not sure why you would have the code and not see that light. I would just clear it and see if it comes back. There is a dipstick so I'm not really sure why there's a sensor. And of course on the newer cars there's only a sensor which is really stupid.

The ABS light is probably a wheel speed sensor.

And the brake circuit issues, I don't know, on the E36 I had that a whole bunch, and it was because the wiring harness that goes up into the trunk lid that flexes gets frayed and arcs on itself, fire hazard. I'm not sure if the brake light wiring on the e53 tailgate if they fixed that. I would think so. I haven't heard of anyone having these problems with the trunk wiring.

I got that thermal oil level sensor code a lot, but never had anything on the dash either. I figured it was just what we control system engineers would call a "spurious trip" or an alarm that wasn't really tripping. I've noticed that with BMW Scanner there were always a handful of codes that would pop up every time you scan, but wouldn't ever show up on the Foxwell, and this might have been one of them in case you are using that to scan. (Catalytic converter heater open circuit alarms were some others)

A failed oil level sensor can turn on the oil level warning or not depending how it has failed. If there's no warning light on the dash you can ignore the fault code if you so choose and just remember to check the oil level and know that the only warning will come if the oil pressure drops. Though the OEM equivalent after market Hella sensor is not that expensive and renew it when the oil is changed and pan is empty anyways.

I'm using a cheap-ish Ancel scanner that has BMW-specific (and others) code libraries. Money is a little tight for now, although I saw a nice Foxwell yesterday on amazon prime days (I don't have prime).