Hi, I'm new here and hope I'm doing this correctly. When I put my 05 roadster away in November everything was working great. Today I started it up for the first time and was surprised to find the rear wing going up, the check engine light on, the ABS light on, BAS ESP light on, the brake light on, and a non working speedometer. I don't have a clue on where to start to solve these problems. Any help would be greatly appreciated. Thanks, Rich

 

It sounds like your battery is very weak. Try charging it but it may be bad.

 

Had a tender on it all winter and it started right up but I’ll check it out. Thanks

 

Zeracer is right. 99% of the time when the spoiler goes up on its own the battery is bad. It has happened to me.

 

Even with a battery tender a battery can go bad !!
I had it happen to me years ago
The wing up when starting is a sure sign of weak battery voltage and many other unusual things occur due to a bad battery
You can even have voltage above 12V with a bad battery

 

Would a weak battery also cause the speedometer not to work?

 

+1 on this also. Wing going up sure is a sign of a weak battery.

Daniel

 

Thanks for the reply. I put a new battery in and the results are the same. I have an appointment on Thursday to see if I can't get this straightened out. I'd rather have figured it out myself, but it might be above my comfortable kowledge level.

 

No. That's a sign the traction control relay's 12 volt feed to the brake controller has failed.

Blown fuse on the RCM
Bad solder connection on the RCM
Bad Traction Control relay on the RCM
.... or similar fault. This is getting to be common with our aging cars.

 

Total waste of money. Cancel the appointment and yank the RCM and send it to DJ in Arizona. For around $60 he will change the relays, flow the board, test it in one of his cars and mail it back.
No local shop will know what is going on with the car - they never do. One guy was told he needed a "new computer, they are$2200 but we can't get them anyway".

I'm telling you, the 12 volt feed to the brake controller has failed. Go ahead, pull the brake controller fuse on any working car and it will do what yours is doing - but its never the fuse, it's the RCM itself.

 

C'mon guys. His speedo does not work - that is not the battery. His "brake controller" is dead, cause it has no power.

 

Wheel speed sensors?

 

I think not. Yank the T/C fuse from the RCM, this simulates a failed relay or fractured solder connection in the feed to the brake controller - you will get EXACTLY what he's getting.
If it was the speed sensors, then he could take it out of park - but since he cant', it sounds like both the interlock and brake controller don't have power - and they are both fed from the traction control relay on the RCM.

My Logical conclusion: He has lost power to the brake controller and interlock due to a failure on the RCM

Try yanking that fuse on the RCM. You will need the tool to get out of park. Take the car for a ride around the block - you car will do just what his is doing. I know.
I tried it one night.

 

Plugs1
I agree with Mark (pizzaguy), bad traction control relay in the relay control module. I can replace the relay and get you back on the road.
Email tighed1@hotmail.com and I'll send you the details.

 

Sorry . . . i did missed the speedo part.

Daniel

 

I saw a photo of DJs new house, it is like a Russian Oligarchs house. He made all that money by repairing RCMs on this forum. I kid you not..
👍

 

77,000 Crossfires at $50 or so each comes to $3.8million.

 

OK... I will agree with others here. DO NOT take this car to a dealer for repair as they have no clue. Let it sit where it is and buy a new RCM on Amazon that will be delivered in a few days and replace the existing one with the new one and see if these problems all vanish. $149 from what I am seeing and it is plug and play. If that fixes the problem you then send your failed RCM to a member here who can refurbish it and you keep it as a spare in the car all the time. Even if this doesn't fix the problem you will have a spare RCM in the car that may as well be a "must have" on-hand with these cars. This is the 1st thing I would do and see if it fixes it before ya start getting crazy with things... You're gonna want a spare RCM with you all the time anyway.

 

Thanks to all of you for your great advice. I’m really pleased with the encouraging responses.

 

ABS lights and no speedo.. Very possibly. After RCM repair.. if the ABS/Dash lights and no Speedo persist: Clean battery ground to frame > Inspect and reseat fuses > Diag/Replace Right Rear Wheel speed sensor