I recently bought another 2004 Crossfire Coupe with 55,000 miles


. It had all the usual problems. The TPMS light was on, the BAS/ESP light would come on, A/C fan wouldn't blow or stop blowing, and the check engine light with the P0401 for the air injector pump. As always I started reading through the tons of threads with all the fixes that people have tried. The problem is, they don't report back with the results of their fixes. So I thought I would share my journey. First, the TPMS. I took it to the local Mercedes specialist. He said all the sensors were transmitting. So he couldn't figure it out. So he took it to the local Chrysler dealership. They said all the transmitters were working but one was too weak for the receiver to read it. So they replaced it and it all works as it should. I found that the reason no independent shop seems to be able to fix the TPMS is because Mercedes did not have TPMS in 2004 for this chasis. So Chrysler added it from their existing technology. Then wrote the software and attached it to the Mercedes software. So to reprogram new sensors the mechanic must have the correct software. Cost was about $225 for one sensor, but it is fixed now. Secondly, the BAS/ESP. Mine was pretty set in its habit. No light on start up, then it came on after about 2 minutes of driving. I had brake lights but no cruise control. Once again I gained the knowledge form this site and decided to replace the brake light switch. $25 from ebay. Boom, problem solved no more BAS/ESP light. Thirdly, the dreaded A/C heater blower motor problems. When I bought the car the fan would sometimes work and sometimes not. So because I had the same problem in my earlier car, I switched out the resistor. It fixed the problem. However, it failed again a few months later causing the fan to run on high even if the key was out of the car. This caused a dead battery. So I assumed it was just a bad resistor and did another replacement. The new one from ebay was $27 and is working fine. Moving on the the forth problem, the P0410. In my case the engine light was very intermittent. So after all the great information contained in this forum I narrowed it down to the Relay Contro Module. (RCM). I didn't go with any of the fixes here, but just ordered up the cheapest one from ebay, $137. Replaced it in about 2 minutes and so far no more engine light what so ever. Some people say don't get the cheap one, go with the OEM. I figured the crap OEM failed once so I would give a repop a try. Now I have the OEM as a backup if the cheapo fails. All these repairs can be done by anyone who can read instructions, watch a youtube video, and operate simple hand tools. One piece of advice for the brake light switch and fan resistor. Get a good mirror to lay on the floorboard to work from. It makes those repairs a lot easier on the back. I would like to thank everyone who contributes to this site as it has saved me thousands of dollars in dealership labor and parts. I hope this helps someone along the way keep their Crossfire on the road and out or the used car auction to become someone else's problem.