Hi All,



I've got a 2011 RR SC that I'm having a truly puzzling electrical issue with.

I'll start by saying I've done everything called for in the electrical troubleshooting guide: Alternator is brand new and tests good, Battery is brand new AGM Interstate Brand and programmed to the vehicle, all grounds and earth points checked and secured, no issues.

Here's what is happening: (locked or unlocked doesn't matter) vehicle will go to "sleep" sometimes immediately, sometimes after an hour or so. Once asleep it will remain that way for a while, sometimes hours. Then it will wake itself up. The LED that illuminates the Hazard switch lights up, the instrument cluster backlight light comes on (the display doesn't start up though), and the actuators in the HVAC system cycle. Then, after 1 minute, it goes back to sleep, then wakes back up immediately and does the same thing. This will go on for minutes or hours, with no explanation.

I've also replaced the final stage resistor, no effect. I've cleared codes and checked for codes. It doesn't matter if there are codes or not, this issue persists.



Keep in mind I have the 2010-12 model which does NOT have a shift selection illuminator LED, it just has the display in the LCD gauge cluster. So the sign I get that it is waking up is the illumination of the Hazard light.



I do get some recurring codes that will come back after being cleared, but not immediately:

B112B-96 (28) Steering wheel module - Component failure - internal failure

B112B-96 (6C) Steering wheel module - Component failure - internal failure

U3000-96 (2E) Control module - Component failure - internal failure (appears to be Audio Amplifier cooling fan issue (intermittent)

U0424-86 (2C) Invalid data received from heating, ventilation and air conditioning control module - Bus signal/message failure - signal is invalid

U0128-00 (2E) Lost communication with parking brake control module (intermittent)



It seems like something in the CANBUS is waking up the BCM but I've pulled fuses for these respective areas to see if it stops the issue, but it does not.

Really hope you all can help point me in the right direction here - do you think I have a bad BCM? I can't find any BCM's on ebay for my model year, the only thing out there seems to be for the BMW era Rovers and mine is the Ford era.



Any ideas?

 

Not an expert, but I would investigate for a short in something like a door switch that wakes the system. If it were mine I'd take a close look at those. I would also pull a couple fuses that relate to the various components like stereo, interior lights, etc. This would stop everything on the circuits related to those fuses from powering on, including waking up. If the problem goes away, its caused by something on those circuits. Then, process of elimination by plugging one back in at a time

Id also recommend a parasitic drain test with a multimeter just to make sure a module isn't staying on.

 

Thanks for getting back with me! I had meant to come back to the forum to provide an update. So I finally sorted out the issue. It was a combination of a bad body control module and a bad battery control module (on the negative battery cable) so I replaced both the cable and the module. My local shop put a new BCM in and *bam!* everything is back to normal and operating properly.
The car goes to sleep and stays asleep.

Thanks again! Happy Rovering!