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Hello everyone, my name is Mike and this is my first post here. I just bought a 2000 DTS and the heated seats dont work, all four of them are out. All the buttons light up and I hear a click, but nothing happens. I pulled the rear seat to check the individual fuses and they are good. Is there a common fuse or circuit that would control them all? It seems weird that all four of the seats are all out. I am hoping that there is a simple non expensive fix, since I have no warrenty.
Thanks.
 

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2005 CTS-V, 1994 Infiniti Q45
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Your already out of warranty???

I recall this same problem on a newer cadillac like yours...... You might do a search..... But more likely the heating pads are shot.... Kinda pathetic on a 3 year old car.... My seat heaters still roast and their 10 years old....

WElcome to the forums.... Thanks for signing up..... :welcome:
 

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2001 DTS, 2005 Mustang GT, 2010 MINI S
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If you dont know....why reply?

Anyways....it would be very strange to have all 4 seat heaters 'fail.' The problem must be something common to all 4 seats.

The seat heaters on the newer cars are replaceable. The mid 90s cars the heater is sewn into the leather part of the seat.

Heres some things to look at......

Heated Seats Description and Operation
Heated Seat Components
The heated seats system consists of 4 heated seats; 2 in the front and 2 in the rear. Each heated seat consists of the following components:

Heated Seat Switch
Heated Seat Module
Seat Back Heating Element
Seat Cushion Heating Element
Temperature Sensor-Cushion
Temperature Sensor-Seat Back
HTDST Fuse 10 A
IGN 3 Fuse 10 A
The driver door module (DDM), passenger front door module (PFDM), left rear door module (LRDM), and right rear door module (RRDM) are also involved in the operation of the heated seats.

Power and Grounds
Battery positive voltage is supplied at all times to the heated seat modules through the battery positive voltage circuit and the appropriate HTDST Fuse located in the rear fuse block. Battery positive voltage is also supplied to the heated seat modules through the ignition 3 voltage circuit and the IGN 3 Fuse located in the rear fuse block. The system will operate only with the ignition switch in the ON position. The driver and front passenger heated seat modules are grounded through the module ground circuits and G302. The left rear and right rear heated seat modules are grounded through the module ground circuits and G301.

Heated Seat Switch and LED Indicators
Each heated seat is controlled by a separate heated seat switch. Battery positive voltage is supplied to the heated seat switch by the appropriate door module.

When the heated seat is off and the heated seat switch HEAT/OFF button is pressed once, the door module supplies a ground through the heated seat high temperature indicator control circuit to the heated seat switch, illuminating the HI temperature indicator. When the switch is pressed a second time, the door module turns off the HI temperature indicator, then supplies a ground through the heated seat medium temperature indicator control circuit to the heated seat switch, illuminating the MED temperature indicator. When the switch is pressed a third time, the door module turns off the MED temperature indicator, then supplies a ground through the heated seat low temperature indicator control circuit to the heated seat switch, illuminating the LOW temperature indicator. After the switch is pressed the fourth time, the door module removes the ground, turning off the LOW temperature indicator.

When the BACK ONLY button is pressed once, the door module supplies a ground through the heated seat back only indicator control circuit to the heated seat switch, illuminating the BACK ONLY mode indicator. When the switch is pressed a second time the door module cancels the back only mode and removes the ground, turning off the BACK ONLY mode indicator.

Operating Modes
There are 2 modes available for heated seat operation; seat cushion and seat back heat, or seat back only heat. When a heated seat temperature signal request is received, the heated seat module will activate both the seat cushion and seat back heating elements. When the heated seat BACK ONLY mode button is pressed once, the heated seat module will deactivate the seat cushion heating element and leave the seat back heating element on. Press the heated seat BACK ONLY button a second time and the heated seat module will reactivate the seat cushion heating element.

Heated Seat Operation
When the heated seat switch HEAT/OFF button is pressed, battery positive voltage is momentarily applied through the switch contacts and the heated seat temperature switch signal circuit of the door module. In response to this signal, the door module momentarily sends a 35 millisecond one shot pulse signal that is pulled low through the heated seat temperature signal circuit of the heated seat module. The heated seat module then applies or removes battery positive voltage through the heated seat element supply voltage to the seat heating elements. The heated seat module counts the signals received from the door module to determine the requested temperature level.

When the heated seat is ON and the BACK ONLY mode button is pressed, battery positive voltage is momentarily applied through the switch contacts and the heated seat back only mode signal circuit of the door module. In response to this signal, the door module momentarily sends a 35 millisecond one shot pulse signal that is pulled low through the heated seat back only mode signal circuit of the heated seat module. In response to this signal, the heated seat module then opens the ground path of the seat cushion heating element through the element control circuit.

Temperature Regulation
The heated seat system is designed to warm the seat cushion and seat back to approximately 42°C (107.6°F) when in the high position, 39.5°C (103°F) when in the MED position, and 37°C (98.6°F) when in the low position. The heated seat module monitors the seat temperature through the temperature sensor signal circuit and the temperature sensors (thermistor) that are located in the seat cushion and seat back. The temperature sensor is a variable resistor, it's resistance varies as the temperature of the seat changes. When the temperature sensor resistance indicates to the heated seat module that the seat has reached the desired temperature, the module opens the ground path of the seat heating elements through the heated seat element control circuit. The module will then cycle the element control circuit open and closed in order to maintain the desired temperature.


Logan
 

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:rolleyes: Because sometimes people need that first reply to get other people to reply..... If thats a bad thing, then let me know!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 

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Discussion Starter #5
Logandiagnostic said:
Anyways....it would be very strange to have all 4 seat heaters 'fail.' The problem must be something common to all 4 seats.
Logan
Thanks for the info, I am not sure what to do past checking the fuses. I was also surprised to see that there wasnt a common fuse for all 4 seats.
Would you say my best bet is to take it to the Caddy service shop?
Thanks again... Mike
 
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