EastBayGeo

My tire pressure monitoring system is acting strange. I start the car and the No Malfunction is shown in the display. After driving the low tire alert comes on. I checked the tires once and they are okay. When I restart the car the display tells me to drive and reset the monitor. The next message usually is a Malfunction Message telling me to drive to the nearest service station. Sometimes I do not get that message and No Malfunctions is displayed. I have low profile tires on the car with 35 psi in the back and 32psi in the front. The car has the AMG package so I guess they are the larger tires. Could the low profile affect the sensors for the monitoring system? I was going to inflate the tires to the highest pressure suggested by the manufacturer (as soon as I find figure out what that is) and see if the problem goes away. When I bought the car it came with the Carfax and it looks like the original owner had the monitoring system replaced a few times in warranty and once out of warranty. Is this issue a design problem maybe?

mf219

You can try resetting it with the button on the dash (if you haven't already), but most likely one (or all) of the batteries are dying. I have an '04 also and mine did exactly what you're describing til it finally just stopped working. You can't just buy the batteries- you have to replace all 4 sensors. The manufacturer's recommended tire pressure should be on the inside of your gas door. Mine states 32 psi rear & 29 psi front. These numbers are for factory or similar tires, of course.

biker349

some rearsearch on tpms sensors that may be helpful. i researched and researched and found multiple sensors that say they will work. prices range from $22 dorman, $46 orotek, $50 itm, $80 vdo and $98 beru. this has been educational. i went with the dorman 974-001. the website listed it for chrysler pacifica. after extensive research i found out it was also listed for many chrysler products including the 300's. after more research i found out it was 315mhz and finally i checked multiple web sites for my car and finally found 2 that listed the dorman 974-001 for 2001-2006 mercedes cl class. multiple other websites listed the dorman as well, but they either didn't show a model #, or used their own part# which of course didn't match dorman's. this has been exhausting and i hope i'm right about the dorman 974-001. for $22 it's worth a shot. any feedback is appreciated. i hope i'm right and that this thread can save some people money.