Heating Cooling Seats INFO

[snowman]

Okay, I have a 2003 EB with an inoperative driver seat climate control. Passenger works fine.

After hours of searching, there seems to be a lot of scattered information in various threads and sites. It's just not in my nature to take a problem to the Dealer$ to fix, and so I will gather up useful info on these seats and put them in this thread for others to use. Please use this thread for information and start a new thread with your own seat problem.

Okay, lets begin...

These seats do not use a resistive wire heating element that you can simply check with a continuity test. Instead they use a Peltier thermo-electric module that depending on the polarity of current flow, will be cool on one side and hot on the other. A fan blows across each side, one directs waste air away from the seat, the other blows the desired air into the seat cushion. A computer monitors all aspects of this system and will shut down and report a code on a detected fault.

Some points to check if you have seat trouble,
~ Make sure your fan filter is clean, and there are no airflow obstructions at the bottom of your seat.
~ Check with a mechanic or someone who can read your DTC (diagnostic trouble codes) to see if the computer is flagging a fault somewhere.
~ Note if your console light illuminates when you call for heat or cold, and how long does it stay on?
~ Unplug harness connectors and examine pins with a flashlight, pins with constant power that are exposed to water from seat washes, coffee spills etc can cause corrosion. If the pins show corrosion then its possible there's a fault where the wire crimps onto the pin.
~ Check the harness connectors behind your seat, rear passengers can get their feet in there and chafe wires or get water/snow in them.
~ There are two fuses for the system, pull them both for a minute and plug them back to see if the module reset will work. One fuse is "always hot" the other is "hot during run."
~ Each seat has it's own climate controlled seat module (CCSM) but they SHARE the same fused circuit. (ie. one fuse powers two seats)
~ The console switch is robust, but have a look for signs of spilled drinks.
~ The fans and the peltier module can be tested out of circuit.
~ Worst case you may have to replace a module or have the dealer reporgram it.

 

[snowman]

Heat Cool Seats internal view

 

[snowman]

Heating Cooling Ford Expedition 2003 schematic view.

In pdf (better) and jpg.

 

[snowman]

Console switch for A/C and Heat internal view..
No coffee in here...

 

[snowman]

FordParts.com Parts Tip: stay cool: know about climate controlled seats
by FordParts.com on Friday, July 22, 2011 at 3:11pm ·

Climate controlled seats have become an option of choice on high-end vehicles over the past few years. Vehicles equipped with these systems are now coming out from under the umbrella of manufacturer warranties and they represent a potential new profit stream for aftermarket repair facilities.

As with all new types of automotive systems, the first step in accurate diagnosis and service is to understand how these seats work. Let’s look at how Ford and Lincoln-Mercury climate controlled seats operate.

There is a thermo-electric device (TED) located within each front seat cushion and backrest.
The TED uses a ''Peltier'' circuit of P-type and N-type semiconductors connected in series using copper electrical conductors. Sandwiched between the semiconductors are insulating ceramic plates.
When current is applied to the TED, one side releases energy as heat, while the opposite side absorbs energy and gets cold.
By reversing the current flow, the hot and cold sides reverse.
The seat temperature is monitored and adjusted by a dual climate control module (DSCM).

Ford uses three different variations of these systems, so you will have to inspect the vehicle in order to identify its exact nomenclature.

During normal operation:

Cabin air is drawn through the seat fan motor and distributed to each of the TED modules located in the seat cushion and backrest.
The TEDs then heat or cool the air.
The air is then directed into the foam pad surface.
Channels in the surface of the foam pad are used to distribute the air along the surface of the seat.
Once the system is activated, the DCSM controls the heating/cooling modes and the fan motor speed based on the control switch settings.

What steps can we take if a customer comes in with a climate controlled seat that’s not heating or cooling? Look for the following:

Does the seat indicator light on the Climate Controlled Seat Panel light up? If not, look for an issue in the power system.
Does the Message Center in the instrument panel indicate a climate control seat fault? If so, use a scan tool to retrieve codes from the DSCM.
Are the blower motors for each seat working?

In fact, blower motor issues are the most common source of climate controlled seat concerns. And in many cases the culprit is the filter on the motors.

Of course the filter is beneath the seat, so the napkins from the fast food chain that get kicked under the seat may get sucked into it. And if the vehicle owner is a pet lover, animal hair will accumulate there. So a filter inspection should be your first step.

Be aware that a restriction of airflow to the TED, may cause it to overheat. This will likely result in DTCs, and cause the seat to enter a recovery mode that disables the TED but runs the blower motor to cool it down. Once the airflow restriction is removed, the seat will resume normal operation.

Although there are other potential faults that can affect the operation of these seats, air filter concerns are by far the most common. Service publications can help when diagnosing individual component or circuit faults, and be aware that when servicing these systems you will also have to interact with the supplemental restraint system.

Climate controlled seat technology varies between car manufactures, but as with all vehicle systems they will require service. Your understanding of these seats, in combination with your automotive service skills can make these seats a new source of profit!

Ford Lincoln Mercury Climate Controlled Seating

 

[snowman]

Ford Climate Controlled Seating Diagnostic Chart

Ford Climate Controlled Seating Diagnostic Chart
Covers climate and seat positioning systems for Expedition and Navigator

Ford Seat Diagnostics and Testing

if the above link is no longer working, pm me and I'll upload the file to a new link.

 

[chrismaddox077]

How do you access the switch on the console for the heated/cooling seat module as listed above? Mine is located within the center console.

 

[NavigatorDude]

Apologies for the grave-digging, but I do have some information that will be helpful for anyone with an '03-'04 Expedition/Navigator with inoperative climate controlled seats and a B2477 DTC.
For some unknown reason, the CCSMs tend to lose their programming at random - searches online point to improper power application such as a jump-start.
The 93C46 EEPROM (circled in red) is responsible for holding the programming on this module. When it errors out with the B2477 code, the EEPROM is almost entirely erased.



Now for the good part - I went to the local salvage yard and harvested a few CCSMs off an Aviator and a Navigator. I desoldered the EEPROM from the Aviator module and found that the programming was still intact, so I dumped it to a BIN file(attached below this post). The Aviator CCSMs do not work with the Navigator, despite being physically identical. However, I flashed the Aviator firmware to the Navigator CCSM's EEPROM and installed it - lo and behold it works!!!!

HOW TO FLASH THE CCSM MODULE:

1. Uninstall the CCSM from your vehicle
2. Desolder the 93C46 EEPROM(circled in red in the picture above)
3. Unzip the firmware and flash the BIN file to the EEPROM using an EEPROM programmer
NOTE: Some EEPROM programmers may need to be modified to work with 93xxx EEPROMs
4. Solder the EEPROM back in to your CCSM
5. Reinstall the CCSM, start your vehicle and enjoy your heated and cooled seats once again!