nickpaesler

Hello all!

I’ve recently been getting a constant dynamic drive malfunction on my five series.

Code: (Status, ARS Module, 0x1 AC) Faulty, Receiver

DME, Transmitter ARS

I’ve done tons of reading that the alternator could be bad, the voltage regulator could be bad, or the battery could be bad. Battery is 2 years old. I don’t believe the alternator has been replaced.

*At the same time, I also have Passenger Restraint System Malfunction*

I’m wondering if anyone else has had this issue and has any advice. Because the code is direct to the module, I’m wondering if maybe I just have a bad dynamic drive module. Over the years the car has had water leak issues so I would not be surprised if the module has seen water in the past.

I’d appreciate any information and advise!

seanjordan20

I would start by unplugging the module and looking for water damage since you said you had water ingress in the past. You would have a code if your alternator wasn't charging to specs. You can also check your voltage to verify.

nickpaesler

Ok gotcha. I think I read the module is in the glove box? Maybe by the fuses?

A friend let me borrow his complex scanner tool but I have a regular ScanGauge, would that be ok to test voltage or do I need a *fancier* scanner? Haha.

habbyguy

All you really need is a cheap multimeter (the kind they regularly give away for free at Harbor Freight, for example). That's more than adequate for measuring battery voltage (and alternator output, which is just battery voltage with the engine running).

Or you can replace your cigarette lighter plug USB charger (you have one, right?) with a model that has a voltmeter, and you can keep an eye on your system voltage before starting, and while driving.

seanjordan20

Just like Habbyguy stated. A $5 voltage meter is good enough to test it.

nickpaesler

Ok coolio. I’ll grab one. And then monitor for surges or if there is too much voltage correct?

seanjordan20

I'd want to see anything in between 13.9v-14.7. Anything higher is bad

nickpaesler

And that range should be off the alternator? Or the module?

nickpaesler

Ok news-went to Auto Zone to have alternator checked. Voltage fine but 'ripple' was at 0.10V, apparently max is supposed to be 0.05V. They said bad alternator. Also said battery is healthy but needs a charge. I've never heard of ripple before, but wondering if that could be enough to make the electric systems go weird.

habbyguy

That voltage range should be at the battery.

Ripple voltage is the variation that's "on top of" the straight DC (steady state) voltage. That is, the voltage is going up and down (in your case) 0.1 volts, no doubt following the rotation of the internals of your alternator. If you looked at a graph, you'd see it as a sine wave most likely - if the alternator had a bad diode, the waveform of the "ripple" would be a lot choppier (and cause more issues).

I honestly have no idea whether 0.1 volts of ripple is enough to cause problems - or not. But my gut tells me that if it WAS causing problems with just that one module, it would be intermittent in nature, not dead to the world.

I'm thinking you're going way, way down a rabbit hole looking for a module problem in a voltage field. ;-)