So I have found a lot of information in the forums on retrofitting a TCU into a Ford. I also found a wiring diagram for a later model Mustang. From that I have a few questions.
In one diagram it appears the in that model year mustang the TCU gets power from pin 16 on the BCM. Will that be the same for my model year or should I look for power elsewhere. In that diagram I did not see where it goes to ground. Not sure if any ground will do or if it has to be a specific point.
In another diagram, it appears that it has two places it has connection to the hscan. Do I have to replicate that or can I pick just one point or can I find the closest point and connect it there to the network.
One last question. Does anyone know the current draw of the TCU. Was contemplating running CAT6 cable from the TCU in the trunk up to the dash and using one twisted pair to carry power to the TCU. I don’t think it would take any more power than an access point getting power over ethernet so it should be fine.
You can use most any constant +12 volts source, does not have to be the BCM.
HS3-CAN, anywhere on the buss. Make sure the polarity is correct and you use twisted pair wire. Stripping out CAT5E works pretty well…
This would suffice. But, CAT6 is rather stiff. CAT5 would be easier for installation. Either cable can carry the power and data just fine as the top end of HS-CAN is 500Mbs.
And a 2015 Mustang was the first year for CGEA 1.3 for that model, so the TCU should work fine.
One other question. There are two FAKRA connectors on the TCU. There is also an antenna splitter/combiner module in the trunk as well. Wish I have better access to Fords information as the few diagrams I do have access to, it is unclear how they are connected or even if the splitter/combiner module is needed.
Some information I have found suggest that you just connect one PIFA antenna to each FAKRA connecter on the TCU. Other implies one PIFA antenna and the other an external GPS/XM(/?LTE) antenna.
Stuff that includes the splitter/combiner module shows it connecting it one of the TCU FAKRA connectors and two antennas one of which looks to be a PIFA and the other I am not sure.
I am probably over thinking this is my problem. I am trying to have both Fordpass and hotspot capabilities. The TCU is one that is on the list with hotspot capabilities. Any help to clarify this would be greatly appreciated.
TCU’s:
J, K and L-series TCU’s come in about 3 flavors…
TCU with no Wi-Fi or location services. One purple antenna port.
TCU with Wi-Fi, no location services. One purple antenna port, one tan antenna port.
TCU with Wi-Fi and emergency services. (EU region) One purple antenna port, one tan antenna port, GSM antenna port for location services.
Antenna ports:
Purple FAKRA port is a cellular TX/RX antenna port for a cellular antenna, style of antenna is dependent on region.
Tan FAKRA port is a cellular RX only antenna port for a cellular antenna, style of antenna is dependent on region. This is used to improve the reception for the wifi hotspot function. This is NOT the Wi-Fi antenna, which is internal to the unit on the circuit board.
GSM antenna port for location services, EU TCU. This is a EU mandated thing.
Hotspot function:
This is for local vehicle Wi-Fi network connected to the vehicle. The TCU hosts the Wi-Fi network. Wi-Fi service is thru a cellular carrier and is a paid service.
So, if you are going to use the Wi-Fi hotspot, you should connect a second antenna to the tan antenna port for more stable Wi-Fi performance. This does not necessarily increase speed, rather it helps prevent dropouts.
As far as the type of antennas to use, the PIFA antennas are far superior in performance than the cheap stick antennas sold by Bingfu and others. It is important to mount the PIFA antennas correctly, with a bolt and fastener to the vehicle metal body which is grounded to the battery. The antenna must have a proper ground plane to function optimally.
You do not have to use any splitters or the like for the TCU antennas, unless you are using a shark fin type GSM/GPS combination antenna. The PIFA antennas work connected directly to the TCU.