Adding Sun Sensor and In-Cabin Sensor for Auto A/C

[jgdiablo]

FYI - I purchased enough wire and connectors to make 5 wiring harnesses to connect the in-cabin temperature sensor, sun sensor, and connect to C2. If anyone is looking for a wiring harness, please IM me.

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[danny01]

FYI - I posted the following in another thread but figured my commentary makes sense to keep here too:

Interesting couple of ideas I can suggest that I just did while installing my wiring harness, the sun sensor, and the in-cabin temperature sensor.

1. according to the instructions, you have to feed the power to the temperature sensor via the the C1 connector - pink/green and black wires. There's so little space there to maneuver and I was really uncomfortable to tap into the C1 wiring harness. I couldn't even figure out how to disconnect the C1 connector to have a little bit more room. Here's what I did - since I purchased the Quadratec 12V accessory tap a while ago for my radar detector, what I did was run my power wires for the wiring harness to the accessory tap (right by the 12V in the center console) - works like a charm, just feeds off the accessory instead of ignition. I can't imagine the cabin sensor would have much of a draw during ACC mode.

2. Since I'm waiting for the dash cap 6GD99TX7AB (correct model number for the sun sensor version - not the '97'), I just left the sun sensor connected to the harness and left it in the footwell area, right near the in-cabin sensor. Obviously, it would keep thinking it's dark outside, but would it matter for the AUTO function? I don't have auto headlights, so what other purpose does it play? I suppose the question is - does it really need to be mounted in the dash or can it just stay connected and in complete darkness?

I apologize for being absent and falling behind on answering questions in this thread.

1. The location in which you feed power to the in-cabin temperature sensor doesn't matter as long as it is a switched ignition feed. In reality, the in-cab sensor only uses the signal and return wires to measure temperature. The ignition and ground wires only turn on the little fan it has in order to draw air in. I used the C1 power and ground because I wanted the wiring to be as close as possible to the factory wiring locations. I also recognize that getting to the C1 connector might be a little tight and uncomfortable for some and your solution is a good alternative.

2. The sun sensor actually has multiple sensors inside its hemisphere shade. Some are used for auto headlights and some are used for climate control. I wouldn't recommend leaving your sun sensor in the footwell area or somewhere where it isn't exposed to the sun; that would defeat the purpose of installing the sensor in the first place. The climate control system uses data from the sun sensor to further refine the cooling or heating strategy and automatically adjusts fan speed, outlet mode, and cooling/heat output depending if it detects that the sun is shining on the cabin directly. Thus, leaving the sensor in the footwell area would tell the climate controls system that there is perpetual darkness and it wouldn't function as accurately. Now, if your Jeep didn't come with auto headlamps, the sun sensor would only be used for climate control purposes.

 

[danny01]

I ordered the 97 and it did NOT have the hole for the sun sensor. I called the online store to review the numbers and they confirmed 99 is the one that has the cutout. You can see the difference in the picture below - #17 vs #18. #17 is the 99, #18 is the 97.

Good catch. I'll note it down in the updated guide soon.

 

[kjl2020]

I apologize for being absent and falling behind on answering questions in this thread.

1. The location in which you feed power to the in-cabin temperature sensor doesn't matter as long as it is a switched ignition feed. In reality, the in-cab sensor only uses the signal and return wires to measure temperature. The ignition and ground wires only turn on the little fan it has in order to draw air in. I used the C1 power and ground because I wanted the wiring to be as close as possible to the factory wiring locations. I also recognize that getting to the C1 connector might be a little tight and uncomfortable for some and your solution is a good alternative.

2. The sun sensor actually has multiple sensors inside its hemisphere shade. Some are used for auto headlights and some are used for climate control. I wouldn't recommend leaving your sun sensor in the footwell area or somewhere where it isn't exposed to the sun; that would defeat the purpose of installing the sensor in the first place. The climate control system uses data from the sun sensor to further refine the cooling or heating strategy and automatically adjusts fan speed, outlet mode, and cooling/heat output depending if it detects that the sun is shining on the cabin directly. Thus, leaving the sensor in the footwell area would tell the climate controls system that there is perpetual darkness and it wouldn't function as accurately. Now, if your Jeep didn't come with auto headlamps, the sun sensor would only be used for climate control purposes.

Now, if I were to buy the switch that has the auto headlight notch in it, would I be able to then obtain power headlights? I know the tazer JL mini can activate it, but I’m not sure if there is anything else needed.

 

[danny01]

Now, if I were to buy the switch that has the auto headlight notch in it, would I be able to then obtain power headlights? I know the tazer JL mini can activate it, but I’m not sure if there is anything else needed.

Given that you have the auto headlamp signal and sensor ground wires connected to C2 of the HVAC module, then yes.

 

[jgdiablo]

I have 4 wiring harnesses prepared and ready to ship to anyone that needs this wiring harness (at a cost). I purchased enough material to make multiple harnesses. Please PM me if you have a need.

 

[jgdiablo]

Given that you have the auto headlamp signal and sensor ground wires connected to C2 of the HVAC module, then yes.

I purchased the auto headlamp unit to try to get it to work, but with OBD JScan, although there's an option there to turn it on, it's not working. My headlamps are always on, even in sunlight. Anyone have any ideas how to fix?

 

[Tpjack]

I have 4 wiring harnesses prepared and ready to ship to anyone that needs this wiring harness (at a cost). I purchased enough material to make multiple harnesses. Please PM me if you have a need.

Evening,
I was wondering if you might still have the wiring harness for the cabin temp sensor and sun sensor? I need to install one on my car in order to get the new HVAC controller I bought to work correctly. I would also like any tips you could offer on going about doing the install.

Thanks in advance

 

[jgdiablo]

Evening,
I was wondering if you might still have the wiring harness for the cabin temp sensor and sun sensor? I need to install one on my car in order to get the new HVAC controller I bought to work correctly. I would also like any tips you could offer on going about doing the install.

Thanks in advance

I do still have some. Please private message me for details and happy to provide guidance on installation.

 

[danny01]

I purchased the auto headlamp unit to try to get it to work, but with OBD JScan, although there's an option there to turn it on, it's not working. My headlamps are always on, even in sunlight. Anyone have any ideas how to fix?

I don't know if you managed to figure this out but I activated mine using the Tazer. Some settings on Jscan might not work properly since they aren't all tested. I know the Tazer route works 100% since I was the one that tested it for Joe.

 

[jgdiablo]

I don't know if you managed to figure this out but I activated mine using the Tazer. Some settings on Jscan might not work properly since they aren't all tested. I know the Tazer route works 100% since I was the one that tested it for Joe.

Unfortunately, no... JScan for Auto headlamp is still not working.

 

[jgdiablo]

FYI - as of 11/15/20, it's now nearly impossible to make this harness. Part 13654871 is out of stock at Mouser and I haven't been able to find it anywhere else.

 

[jgdiablo]

I think I may have come up with another option for those that need to leverage a self-made wiring harness. I'm thinking of using the wiring harness that comes in Wranglers that have sun sensor/cabin temperature sensor capabilities from the factory. According to my research, the wiring harness that's used in those Wrangler models is 68301852AA (~$70 online).

I'm thinking we'd just use the portion of the harness for the three connectors:
Connector to the sun sensor
Connector to the cabin temperature sensor
Connector (C2) to the HVAC module

Here's the only caveat - the factor C2 connector is getting the two power/ground wires from the C1 connector. Unless you're going to consider replacing the entire wiring harness, I would leave all of the other connectors not plugged in, use the three above, and cut the power/ground wires between C1 and C2 and splice two new wires and get power from the existing C1 as per instructions or run to the Accessory power as I did.

I plan to try this out...

 

[bldofia]

I think I may have come up with another option for those that need to leverage a self-made wiring harness. I'm thinking of using the wiring harness that comes in Wranglers that have sun sensor/cabin temperature sensor capabilities from the factory. According to my research, the wiring harness that's used in those Wrangler models is 68301852AA (~$70 online).

I'm thinking we'd just use the portion of the harness for the three connectors:
Connector to the sun sensor
Connector to the cabin temperature sensor
Connector (C2) to the HVAC module

Here's the only caveat - the factor C2 connector is getting the two power/ground wires from the C1 connector. Unless you're going to consider replacing the entire wiring harness, I would leave all of the other connectors not plugged in, use the three above, and cut the power/ground wires between C1 and C2 and splice two new wires and get power from the existing C1 as per instructions or run to the Accessory power as I did.

I plan to try this out...

Have you done this yet? How did it turn out? Having the same issues with procuring all the parts to build the harness, was thinking wrecking yard for the harness but if your suggestion works then I may go that route.

 

[jgdiablo]

Have you done this yet? How did it turn out? Having the same issues with procuring all the parts to build the harness, was thinking wrecking yard for the harness but if your suggestion works then I may go that route.

Part ordered. I’ll try it out this weekend.