Heated/Cooled Seat not heating issue

[simonb65]

Has anyone with the headed/cooled seats had issues with one seat not heating. Specifically, the button LEDs light but there is no relay click. This was intermittent a few weeks ago, now doesn't click on at all. I'm suspecting wiring( possibly under the seat). There have been few 2015+ F150 and Mustang issues with melted ground pins on the seat climate controller under the seat, so may be the same. I've not looked yet. Just wondering if anyone has the service manual pages for the climate front seats. Don't want to unplug anything , to check, and end up setting the airbags or pre-tensioners off!!

[Trent Edge]

I'm adamant that the heating on the drivers seat on my car has got worse over the years. I can barely feel it now where as passenger seat there's a noticeable difference. Just checked mine and the very noticeable clicking is still there when you switch the heating or cooling on.

[simonb65]

Well, for those that read this an have a similar issue, the fault is not the same as the F150 and Mustang ... on the Edge, they use 2 ground pins to spread the current, so a burnt pin is not the issue.

I have hooked up Forscan and the DTC is B272D-60, which is a 'differential' temp problem between the back rest cushion and the seat cushion on the passenger seat. Also testing using the PIDs feature of Forscan shows that when you put the passenger heated seat on, the seat cushion temp rises, but the seat back only rises a few degrees. Hence the difference between them is greater than 60DegC and the system shuts down with the fault. Drivers seat works as expected.

Next steps is to fault find and determine if it's a faulty heater/blower in the seat back. That can be done by looking at the resistances, etc of the wiring from the ECU through the blower (plus checking that no wiring is loose, shorted or broken). If the seat back blower assembly needs replacing, stripping the seat back down to get to it is a job and a half! Maybe wait until it stops snowing before I venture out there again ...

[MasterTechTip]

I have had a vignale Mondeo (heated and cooled seats) with all 4 heating elements (2 passenger and 2 driver) just give up at the same time. Monitored the temperature of the seats and found hardly any increase in temperature. Replaced all 4 units and it worked fine after that. 

[Trent Edge]

On 2/7/2021 at 9:39 PM, simonb65 said:

Well, for those that read this an have a similar issue, the fault is not the same as the F150 and Mustang ... on the Edge, they use 2 ground pins to spread the current, so a burnt pin is not the issue.

I have hooked up Forscan and the DTC is B272D-60, which is a 'differential' temp problem between the back rest cushion and the seat cushion on the passenger seat. Also testing using the PIDs feature of Forscan shows that when you put the passenger heated seat on, the seat cushion temp rises, but the seat back only rises a few degrees. Hence the difference between them is greater than 60DegC and the system shuts down with the fault. Drivers seat works as expected.

Next steps is to fault find and determine if it's a faulty heater/blower in the seat back. That can be done by looking at the resistances, etc of the wiring from the ECU through the blower (plus checking that no wiring is loose, shorted or broken). If the seat back blower assembly needs replacing, stripping the seat back down to get to it is a job and a half! Maybe wait until it stops snowing before I venture out there again ...

Hi Simon, did you look into this any further?

[simonb65]

2 hours ago, Trent Edge said:

Hi Simon, did you look into this any further?

No, other than looking at the service manual to see what you need to strip out of the seat to check the heater and fan. Both are behind the curtain airbag assembly in the side bolster, so it's a battery off, disconnect the seat ECU and seat out to strip things down. I could just check the heating element resistance from the connector under the drivers seat, but the airbag stuff makes me a bit nervous! ... and it's only the passenger seat, so it doesn't bother me 99% of the time! Just be nice to get it fixed.

I will post more info on here when I finally get round to stripping things down!