harness more important than the hitch
I mention the harness as I regard it as being of more significance than the hitch. I say that because once installed, the harness is there all the time and can affect operation of the vehicle regardless of if a trailer/hitch is attached or not.
In Europe there is some rule that says the operation of trailer signal lights has to be monitored and a dash warning show up a fault. As such Land Rover, Mercedes, Audie, BMW et all tend to send microvolt pulses down the signal light circuit to see if the tungsten filaments are still there.
What is amusing is that in our pre LED 3's, trailers with LED "bulbs" are not seen. This in reality means to the vehicle that there is no trailer attached and hence no signal light problem and therefore no adverse warnings will be generated.
Normally one would regard that as "who cares" but for our 3, that means the automatic operation of the air suspension system in not inhibited and hence your trailer can be subject to hitch height changes when you are driving - not always the best. Also if the trailer is not sensed, then when in reverse, the reverse sounders will beep as the trailer is seen as an obstruction. That is just a nuisance thing but there are also tranny shift patterns and other stuff that benefits from knowing a trailer is attached.
Worse is a defective or off spec harness that starts to talk to the computers and you do not know there is even a discussion in progress, let alone what it is about - well you might see the affects of it, much like a defective brake light switch as the rear circuits are all tied together - and you will not beable to guess from where the problems are generated.
I mention the harness as I regard it as being of more significance than the hitch. I say that because once installed, the harness is there all the time and can affect operation of the vehicle regardless of if a trailer/hitch is attached or not.
In Europe there is some rule that says the operation of trailer signal lights has to be monitored and a dash warning show up a fault. As such Land Rover, Mercedes, Audie, BMW et all tend to send microvolt pulses down the signal light circuit to see if the tungsten filaments are still there.
What is amusing is that in our pre LED 3's, trailers with LED "bulbs" are not seen. This in reality means to the vehicle that there is no trailer attached and hence no signal light problem and therefore no adverse warnings will be generated.
Normally one would regard that as "who cares" but for our 3, that means the automatic operation of the air suspension system in not inhibited and hence your trailer can be subject to hitch height changes when you are driving - not always the best. Also if the trailer is not sensed, then when in reverse, the reverse sounders will beep as the trailer is seen as an obstruction. That is just a nuisance thing but there are also tranny shift patterns and other stuff that benefits from knowing a trailer is attached.
Worse is a defective or off spec harness that starts to talk to the computers and you do not know there is even a discussion in progress, let alone what it is about - well you might see the affects of it, much like a defective brake light switch as the rear circuits are all tied together - and you will not beable to guess from where the problems are generated.
