FAQ
TL;DR: BMW E46 central locking is triggered by two negative pulses (“2× ground”). “Control 2x mass from the driver's door.” [Elektroda, SKRZYNIA, post #19813115]
Why it matters: This lets you wire an aftermarket remote safely without frying the comfort module; this FAQ shows where and how for DIYers.
Quick Facts
- Aftermarket remotes can tie into the driver’s door harness; this is a verified E46 practice. [Elektroda, SKRZYNIA, post #17033714]
- Some posts cite comfort-module pins 54 (open) and 36 (close), but use with caution. [Elektroda, moto-kord, post #16991211]
- One user nearly burned the module when experimenting on those pins—miswiring risk is real. [Elektroda, tuptusiowie90, post #19808850]
- The center console lock switch is a 5‑pin unit next to the hazards. [Elektroda, 1988zajac1988, post #16991243]
- E46 Convertible report: pins 13 and 51 show brief +12 V pulses; some door-connector cavities are empty. [Elektroda, jastrzab0, post #18083257]
Where should I connect an aftermarket remote in a BMW E46?
Tie the remote’s lock/unlock outputs into the driver’s door wiring harness. This tap point is proven to work on E46. [Elektroda, SKRZYNIA, post #17033714]
Is the E46 central locking positive or negative trigger?
It uses two negative triggers (2× ground) for lock and unlock from the driver’s door. “Control 2x mass from the driver’s door.” [Elektroda, SKRZYNIA, post #19813115]
Which comfort‑module pins are often mentioned for lock/unlock?
Some posts reference pins 54 (open) and 36 (close) on the module behind the glovebox. Verify before applying signals. [Elektroda, moto-kord, post #16991211]
Is it safe to drive the comfort module directly on pins 54 and 36?
Proceed carefully. A user reported almost burning the module when trying that approach. Use door-harness negative triggers instead. [Elektroda, tuptusiowie90, post #19808850]
Can I wire into the center console lock button?
Yes, but identify each of the 5 switch pins correctly. Expect no turn‑signal flash if you only tie lock/unlock. [Elektroda, 1988zajac1988, post #16991243]
Where is the comfort (GM5) module located on E46?
Behind the passenger compartment/glovebox area referenced in posts discussing pins 54 and 36 for lock control. [Elektroda, moto-kord, post #16991211]
I have an E46 Convertible. Why don’t pins 54/36 behave as expected?
Convertible wiring can differ. One report shows +12 V pulses on pins 13 and 51, and missing door‑plug pins. [Elektroda, jastrzab0, post #18083257]
My fuse blows when I connect to pins 13/51; what’s happening?
You’re likely feeding +12 V where the system expects a different trigger. That caused a blown fuse in a report. [Elektroda, jastrzab0, post #18083257]
What does “2× mass” mean in this context?
It’s BMW‑speak for two ground pulses. Your remote’s outputs should provide brief negative pulses for lock and unlock. [Elektroda, SKRZYNIA, post #19813115]
Quick 3‑step: how do I wire the aftermarket remote on an E46?
- Mount the controller securely near the driver’s kick panel.
- Splice its lock/unlock negative outputs into the driver’s door harness.
- Test pulse timing, then insulate and secure all joins.
“Always do this model and it works!!” [Elektroda, SKRZYNIA, post #19813115]
Can I retrofit remote locking if my E46 came with only keys?
Yes. Owners add a universal remote controller and tie into the existing door harness to drive central locking. [Elektroda, 1988zajac1988, post #16991164]
Will I get hazard‑light flash when using only the lock/unlock lines?
No. The poster tapping the console switch noted lock/unlock without turn‑signal confirmation when wired that way. [Elektroda, 1988zajac1988, post #16991243]
Any model‑specific gotchas or edge cases to expect?
Yes. Convertible harness cavities may be empty, and experimenting at the module can damage it. Verify pins first. [Elektroda, jastrzab0, post #18083257]
What’s a safe rule of thumb for signal polarity and count?
Plan for two signals, both negative pulses, from the driver’s door harness. This matches repeated expert advice. [Elektroda, SKRZYNIA, post #19813115]
Do I have to remove the door panel, or can I work at the glovebox?
Working at the door harness avoids glovebox‑module risks and aligns with experienced installers’ guidance. [Elektroda, SKRZYNIA, post #17033714]
together with the emergency lights - I will add that there are 5 cables).
together with the emergency lights - I will add that there are 5 cables).
