Can anyone help with this issue. I have a battery drain problem so I disconnected the RF receiver and still a dead battery. Sat in the car for a while after a drive and noticed the BeCM does not sleep. (little red light next to park never goes out).

Any ideas anyone?

 

What year is you RR?

 

its a 2001 se with the 4.6 and the EAS was removed some time ago and replaced with coils. ( Before I acquired it) just some other issues that might be related is the drivers heated seat has power to the connector whether the switch is on or off.

 

Could be as simple as that. I had a 1999 P38 RR and when the interior light switch broke I popped in a push button switch I had lying around and ended up with a dead battery overnight. Not because the light was on, but because the switch wasn't a momentary contact type. The BECM uses a momentary signal to change the state of the various features. A momentary pulse from the dome-light switch makes the BECM change the state of the light so if it's on it turns it off and if it's off it turns it on. The switch I put in made the light change state but then the BECM continued to receive a signal from the switch so it never went to sleep. As a result it continued to stay awake, killing the battery. If you have a switch somewhere that is constantly making contact then the BECM won't sleep.

 

That would tell me that a transistor in the BeCM is bad though correct?

 

i noticed the same thing on my 99 but after 5-minutes the light went out

 

Did you have the key in the ignition (ignition off) when you noticed the BeCM on?

 

no i did not