Looking for Sun Load Temp Sensor

[kep5niner]

Team:

Been troubleshooting the DATC system in my '03 EB, and I think I've got it narrowed down to one last item that could possibly make my system finally operate correctly. First:

THE PROBLEM:

It seems in the summer, my AC doesn't blow as cold as it should, and in the winter the heat doesn't warm as it should.

TROUBLESHOOTING:

I started by pulling the DTC codes froim the DATC. Initial indications resulted in failed blend door and mode door actuaters. No other DATC DTCs at the time. I replaced those, and the problem persisted. I took it to the dealership, and they ensured the 134a was topped-off, and it took very little. Still no solution. A few months later I took it to another dealer, and they pulled DATC DTC B1259 - the sun sensor. The dealer stated it was either the sun sensor or the DATC system itself, which they could order neither. At my recommendation, they smoked the system and found no leaks. They still happily charged me $400 for diagnosing a problem they couldn't fix...

PARTS REPLACED:

I replaced the blend door and mode door actuators last year, as well as the hot water valve. New coolant, thermostat and hoses with the engine swap last year. I also replaced the hot-water valve with a Motorcraft replacemnt. Now I've replaced the DATC itself (from the eBay), as well as the solenoid assembly in the center console - PN 2L1Z-19D611-AA. Ran the DATC diagnostics, and it still comes up with B1259 - that sun sensor.

From my research, the PN for the sun load sensor is YF1Z-13A018-AA. The production date for my truck was 02/19/2003. For the life of me, I can't find one of these. Can someone point me in the right direction to find the correct sun load sensor (or its superseded PN)? Thanks fellas!

 

[Hamfisted]

Probably a junkyard item. They used the same one in all the Gen2 Expies & Navs, 04-08 F-150s, '00-'07 Taurus. So hopefully you can find one that's salvageable.








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[whtbronco]

Looks like the 2003-2011 Crown Vic and Grand Marquis use the same sun load sensor as well. At least you have a nice selection of models and years to look for. I couldn't find one either.

 

[kep5niner]

Thanks for the help guys. Next time I layover in ATL, there’s a pick-N-pull right down the road from the hotel. I’ll go digging!

 

[kep5niner]

Here’s an update. Found a sun load sensor from the junk yard, and it resolved the DATC code. So now, according to the DATC, all is well. Still doesn’t blow my socks off with the heat, but it’s more than nothing.

 

[Hamfisted]

Sounds good ! Any difference between front and rear heat output ? ( If the rear heat temp actuator is working...)

 

[kep5niner]

Honestly I haven’t got back there to see how the rear heat, or even AC in the summer, is doing. That may be a whole other ball of wax.

 

[kep5niner]

Following up, I did replace the blend door actuators in the rear last year. If i recall correctly, there were 2. No clicking anymore. I’m presuming the rear HVAC simply draws the same hot coolant than the front, but not sure if there are other failure point(s) in the rear system.

 

[whtbronco]

Yeah the coolant is shared, the heater hoses T off under the hood for the rear heat. Pretty much same failure points out back as up front. Heater core and hoses. The only coolant hose leak I have had thus far was the 2 hoses in the back that go through the floor pan.

I'm gonna replace all the hoses up front soon.