Hey guys! I have an automatic 06 convertable base trim (I think...interior looks really cheap) that wont try to start. I got it last summer, it initially had intermittent trouble starting. Replaced the battery, fixed the issue for a bit. Problem came back, cleaned the ground clamp and the issue was fixed until I parked the car for winter. Finally had some good weather so I tried to start car - problems back. No start, no crank. Fan races. Charged and tested battery, its at 12.97 volts. I installed a new ground cable and rcm - still no crank. Going to get some e-torx sockets later so I can do the engine block ground mod and eliminate bad ground as a possibility. The jumper ground under the car is pretty rusty, could a bad ground cause these issues? If not, any idea what else it could be?

 

No starter engagement with a high speed engine fan is in indication that the RCM's "Engine Control Relay Output" is faulty. The point here is that your fan control module is powered up, but the ECU is not powered up.

I'd suspect the RCM, both the solder points as well as the ECR relay. Also, verify the ECR fuse on the RCM is not blown (simply check all RCM fuses).

 

I put a brand new rcm in already, maybe I just got a bad one? Just tested every fuse on the car, including on the rcm, and they are all good.

 

Time to get the volt meter out and find out what is missing here. Again, a high speed fan indicated the FCM is powered up, but it is not getting its 'tickle' pulses from the ECU.

WHY NOT?

And the starter won't engage.

WHY NOT?

BOTH of these indications point to an ECU that is not 'running', that is, is not powered up. If you look in the wiring diagram of the service manual, go to "power distribution" and look for all the 12 volt inputs to the ECU. I'd bet you MONEY that at least one of those inputs is dead, that is, not at 12 volts or so, but at essentially zero volts.

If your RCM is used, it's probably bad. If your RCM is actually NEW, you must figure out why you are getting symptoms of no "engine control relay output" from the RCM to ECU.

 

Thanks for all your help! I cracked open the "new" rcm on a whim, and the solder work is the worst Ive ever seen. I think someone tried to repair their rcm, failed, ordered a new one, swapped the case, then returned it. I started an exchange through Amazon, so hopefully when the new one comes in that will solve the issue.

 

I am confident you are right.
To me, it's just another reason to avoid Amazon. I like PartsGeek, FCPEuro, Needswings, etc.

Dishonesty is almost the default position of what seems like the majority of Americans these days. Who needs character when dishonesty works so well?

 

That's what it was. Got the new rcm in and it fired right up. Thanks again for your help!

 

This was a dead give-away that the ECR output from the RCM was bad!

 

I would add Rock Auto to that listing of reliable suppliers.