Honda Car Forum

Hello,

Does anyone know where I might be able to read the wireless FOB
information? I'm basically looking to get indication when the keyless
"lock" command is received, as is the keyless "unlock" command.

I plan to run the signals into electronics for a project. If I were
to simply grab the 12vdc going to the lights, that would be no good as
it would be triggered at other times.

Hopefully it can be had under the dash?

Is there a module the controls the locks, and has separate inputs for
lock and unlock and trunk from the wireless receiver?

The more I think about it, a module to detect rain and roll up
windows/shut sunroof would be handy also.

TIY!!!

ethan@757.org wrote:
>
> Hello,
>
> Does anyone know where I might be able to read the wireless FOB
> information? I'm basically looking to get indication when the keyless
> "lock" command is received, as is the keyless "unlock" command.
>
> I plan to run the signals into electronics for a project. If I were
> to simply grab the 12vdc going to the lights, that would be no good as
> it would be triggered at other times.
>
> Hopefully it can be had under the dash?
>
> Is there a module the controls the locks, and has separate inputs for
> lock and unlock and trunk from the wireless receiver?
>
> The more I think about it, a module to detect rain and roll up
> windows/shut sunroof would be handy also.

I don't know the specifics of the 01 Accord, but in recent vintage
Hondas the receiver is integrated with the door lock control module.
Thus the lock and unlock signal pulses may not be easily accessible. You
could read the door lock actuator wires instead. Each actuator has two
wires (well, two wores that count, some times there are additional wires
for switches inside the actuator), applying 12 V with one polarity
unlocks, the other polarity locks. Tapping into these wires in the
driver's door will work (any other door may not, since with the priority
unlock feature it is possible to unlock the driver's door only, the
remaining actuators will not se any action). In the old days, the
actuator wires were accessible under the dash as well, on the '01 the
signals may (and I don't know if this is the case) be multiplexed onto a
bus going into the door, and thus hard to access.

Typically both actuator wires are grounded at rest, and lock and unlock
is done with a positive pulse on one lead or the other. Pulse length is
usually on the order of 0.5 - 1.0 seconds. You could tap into the wires
directly, or you could use two polarized opto-couplers, one in each
direction.

There is a Haynes manual for the 98 - 02 Accord (#42014). They usually
have decent wiring diagrams. I have found Haynes manuals at several
public libraries.

"Randolph" <trash@junkmail.com> wrote in message
news:41E5A651.2194BC0A@junkmail.com...
>
> ethan@757.org wrote:
>>
>> Hello,
>>
>> Does anyone know where I might be able to read the wireless FOB
>> information? I'm basically looking to get indication when the keyless
>> "lock" command is received, as is the keyless "unlock" command.
>>
>> I plan to run the signals into electronics for a project. If I were
>> to simply grab the 12vdc going to the lights, that would be no good as
>> it would be triggered at other times.
>>
>> Hopefully it can be had under the dash?
>>
>> Is there a module the controls the locks, and has separate inputs for
>> lock and unlock and trunk from the wireless receiver?
>>
>> The more I think about it, a module to detect rain and roll up
>> windows/shut sunroof would be handy also.
>
> I don't know the specifics of the 01 Accord, but in recent vintage
> Hondas the receiver is integrated with the door lock control module.
> Thus the lock and unlock signal pulses may not be easily accessible. You
> could read the door lock actuator wires instead. Each actuator has two
> wires (well, two wores that count, some times there are additional wires
> for switches inside the actuator), applying 12 V with one polarity
> unlocks, the other polarity locks. Tapping into these wires in the
> driver's door will work (any other door may not, since with the priority
> unlock feature it is possible to unlock the driver's door only, the
> remaining actuators will not se any action). In the old days, the
> actuator wires were accessible under the dash as well, on the '01 the
> signals may (and I don't know if this is the case) be multiplexed onto a
> bus going into the door, and thus hard to access.
>
> Typically both actuator wires are grounded at rest, and lock and unlock
> is done with a positive pulse on one lead or the other. Pulse length is
> usually on the order of 0.5 - 1.0 seconds. You could tap into the wires
> directly, or you could use two polarized opto-couplers, one in each
> direction.

Actually, unless things have changed recently, Honda lock wires are ground
activated. Meaning that they lock (or unlock) when ground is applied to the
control wires. IIRC, they are light-blue and white and located behind the
drivers kick panel.

Seth wrote:
>
> "Randolph" <trash@junkmail.com> wrote in message
> news:41E5A651.2194BC0A@junkmail.com...
> >
> > ethan@757.org wrote:
> >>
> >> Hello,
> >>
> >> Does anyone know where I might be able to read the wireless FOB
> >> information? I'm basically looking to get indication when the keyless
> >> "lock" command is received, as is the keyless "unlock" command.
> >>
> >> I plan to run the signals into electronics for a project. If I were
> >> to simply grab the 12vdc going to the lights, that would be no good as
> >> it would be triggered at other times.
> >>
> >> Hopefully it can be had under the dash?
> >>
> >> Is there a module the controls the locks, and has separate inputs for
> >> lock and unlock and trunk from the wireless receiver?
> >>
> >> The more I think about it, a module to detect rain and roll up
> >> windows/shut sunroof would be handy also.
> >
> > I don't know the specifics of the 01 Accord, but in recent vintage
> > Hondas the receiver is integrated with the door lock control module.
> > Thus the lock and unlock signal pulses may not be easily accessible. You
> > could read the door lock actuator wires instead. Each actuator has two
> > wires (well, two wores that count, some times there are additional wires
> > for switches inside the actuator), applying 12 V with one polarity
> > unlocks, the other polarity locks. Tapping into these wires in the
> > driver's door will work (any other door may not, since with the priority
> > unlock feature it is possible to unlock the driver's door only, the
> > remaining actuators will not se any action). In the old days, the
> > actuator wires were accessible under the dash as well, on the '01 the
> > signals may (and I don't know if this is the case) be multiplexed onto a
> > bus going into the door, and thus hard to access.
> >
> > Typically both actuator wires are grounded at rest, and lock and unlock
> > is done with a positive pulse on one lead or the other. Pulse length is
> > usually on the order of 0.5 - 1.0 seconds. You could tap into the wires
> > directly, or you could use two polarized opto-couplers, one in each
> > direction.
>
> Actually, unless things have changed recently, Honda lock wires are ground
> activated. Meaning that they lock (or unlock) when ground is applied to the
> control wires. IIRC, they are light-blue and white and located behind the
> drivers kick panel.

Yes, the control wires are ground activated, but the control wires are
not the ones driving the actuators. The actuators are driven with 12
Volts, negative one side positive the other for lock, reversed for
unlock.

"Randolph" <trash@junkmail.com> wrote in message
news:41F0CE9E.2884811E@junkmail.com...
>>
>> Actually, unless things have changed recently, Honda lock wires are
>> ground
>> activated. Meaning that they lock (or unlock) when ground is applied to
>> the
>> control wires. IIRC, they are light-blue and white and located behind
>> the
>> drivers kick panel.
>
> Yes, the control wires are ground activated, but the control wires are
> not the ones driving the actuators. The actuators are driven with 12
> Volts, negative one side positive the other for lock, reversed for
> unlock.

And for what he's looking, in my opinion, that is over complicated. The OP
just wants a "signal", one for lock and one for unlock. The control wires
do just that, already separated by function (lock/unlock) and are low
amperage, perfect for connecting directly to a logic circuit for activation
detection. That's why almost all car alarm manufacturers go for these wires
and not directly to the actuator wires.

Seth wrote:
>
> "Randolph" <trash@junkmail.com> wrote in message
> news:41F0CE9E.2884811E@junkmail.com...
> >>
> >> Actually, unless things have changed recently, Honda lock wires are
> >> ground
> >> activated. Meaning that they lock (or unlock) when ground is applied to
> >> the
> >> control wires. IIRC, they are light-blue and white and located behind
> >> the
> >> drivers kick panel.
> >
> > Yes, the control wires are ground activated, but the control wires are
> > not the ones driving the actuators. The actuators are driven with 12
> > Volts, negative one side positive the other for lock, reversed for
> > unlock.
>
> And for what he's looking, in my opinion, that is over complicated. The OP
> just wants a "signal", one for lock and one for unlock. The control wires
> do just that, already separated by function (lock/unlock) and are low
> amperage, perfect for connecting directly to a logic circuit for activation
> detection. That's why almost all car alarm manufacturers go for these wires
> and not directly to the actuator wires.

Absolutely, the signal wires are the easiest to use, if they are
available. With the remote receiver built into the door lock control
module, the signal wires may not be available externally. If you gave
specific information to the contrary, the OP would probably be happy to
hear it.

The actuator wires not difficult to use. In most cars, with the system
at rest, both wires are grounded (not left open). The functions are
separated, a positive pulse on one wire means lock, a positive pulse on
the other means unlock.

If the OP wants info from the remote control only, sensing the actuator
wires will not work. Sensing the actuator wires, you will get the same
lock and unlock signals no matter what caused the lock or unlock (key,
manual switch, remote control etc.).

The current flow in the wires is of no consequence. If there are 25 Amps
or 5 milliamps, the logic circuit would still just sense a 12V signal.

Much thanks everyone for the info. I could probably use use an
optoisolator + resistor tied to each one of the lock leads to alert the
embedded computer as to power headed for the door solenoids.

Is the lock module on the passenger kick panel? I found that module
when running some other cables.