Cooled Seat Issue

[GTEyes]

Hi Everyone,

 

I am noticing an anomaly with my 2024 Edge ST's cooled seat functionality and how the vehicle's Auto Start/Stop system is impacting it.

 

Often, when the start/stop system turns the engine off in traffic, the cooled seat fan also stops working (but the indicator still says it's "on" in the HVAC screen).

If I toggle the cooled seats off, then turn back on, it starts again but it seems like the start/stop system is triggering the cooled seat fan to turn off for some reason.

 

Since the HVAC screen is still showing it's on, and it's an intermittent issue, I am thinking this is not usual operating procedure.

 

I've done some searches on the site here and don't see any threads discussing this issue.

 

Anyone experience something similar?

 

Edited June 12 by GTEyes

[garycrist]

If the battery is low on charge, then load shedding takes placeandr electrical accessories are switched off. My advice is to turn off

the ASS feature as it will shorten the life of the turbos.

 

OOHH a Ford joke! If one does not switch off one's ASS his blower breaks! 🤣

[Davidoo]

I'm pretty sure this is normal behavior.  I have a 22 ST.  If I have the A/C on and the stop/start cuts off the engine at a light, I can hear the main blower fans slow down and the cooled seat noise disappear as well.  Otherwise, it would pull too much load off of the 12 volt battery.  This only lasts up to at most 30 seconds for me, as I will hear the engine come back on and all blowers go back up if I sit at the light very long.  I'm in Phoenix and it has been over 110 degrees recently, and in most cases the start/stop feature doesn't even engage in that heat because I'm sure there are programming parameters such as ambient temperature and what you have it set on in the car.  I don't think anything is wrong with yours.  I'm assuming all your fans come back on to what they were set for if you leave the controls alone and press the accelerator and the engine starts?

[GTEyes]

Thank you guys for replying so quickly.

 

I don't believe they turn back on by themselves when they do this behaviour, so they are staying off until I turn them off and then back on through the HVAC control. I will verify that today.

 

Great Dad Joke, @garycrist

[GTEyes]

As expected with these sort of things, it didn't do it a single time on the drive home. However, I had the HVAC system off, so perhaps that adds some strength to the idea of electric loading being the cause. They did replace the battery in my Edge before I took delivery 🤔

 

I will continue to monitor and see what I observe!

 

Side note, had to pull away quickly from a stop sign and I am still so impressed with the torque of this engine. It's a gem!

[Haz]

From the 2024 Edge Workshop Manual...

 

Auto-Start-Stop System

The Auto-start-stop system helps reduce fuel consumption by automatically shutting off the vehicle’s engine while the vehicle is at a complete stop and restarting the engine when the brake pedal is released. The system can be disabled through the auto-start-stop control switch on the instrument panel centerstack. The Auto-start-stop system is automatically enabled whenever the ignition is turned on.

 

The engine automatically restarts when:

• the brake pedal is released.
• the Auto-start-stop system is disabled through the auto-start-stop control switch on the instrument panel centerstack.
• the battery has a low state of charge.
• it is necessary to maintain interior comfort.
• the blower fan speed is increased or the climate control temperature is changed.
• an electrical accessory is turned on or plugged in.
• there is low brake vacuum.

The Auto-start-stop system may not turn the engine off under these conditions:

• the HVAC system is in A/C, heat or defrost modes.
• the rear defroster is on.
• the battery has a low state of charge.
• the battery temperature is below 5°C (41°F) or above 60°C (140°F).
• the engine temperature is below 46°C (115°F).
• the engine temperature is below 60°C (140°F) and the HVAC system is in heat mode.
• the gear selector is not in Drive or Sport Mode.
• the steering wheel is turned rapidly or is at a sharp angle.
• vehicle speed of greater than 4 km/h (2.5 mph) for more than 2 seconds has not occurred.
• the vehicle is on a steep road grade.
• elevation is approximately above 3,048 meters (10,000 feet).

 

And...

 

Direct Current/Direct Current (DC/DC) Converter Control Module - System Operation and Component Description

 

System Diagram

 

System Operation

Network Message Chart

 

Broadcast Message	Originating   Module	Message Purpose
Engine status	PCM	Used to indicate the type of cranking event occurring. If the signal is state 2, Engine Auto Stopped, then the next commanded crank is to be supported. If the signal is state 0, Engine Off, the next crank will be a key crank and the Direct Current/Direct Current (DC/DC) converter control module will not support.

 

The Direct Current/Direct Current (DC/DC) converter control module, also known as the Voltage Quality Module (VQM), is responsible for boosting battery voltage to specific components on vehicles equipped with the auto-start-stop system. When the ignition is turned on the Direct Current/Direct Current (DC/DC) converter control module initializes after receiving the Run/Start power feed from the BCM controlled run/start relay.

 

While in stand-by mode the Direct Current/Direct Current (DC/DC) converter control module performs self-diagnostics and is not producing any boost output voltage. The Direct Current/Direct Current (DC/DC) converter control module is simply passing battery voltage straight through to downstream loads when it is in stand-by mode.

 

The Direct Current/Direct Current (DC/DC) converter control module continuously communicates it's status to the PCM via High Speed Controller Area Network (HS1-CAN). If the Direct Current/Direct Current (DC/DC) converter control module is overloaded, overheated, or other faults are present the PCM disables the auto-start-stop system. If a fault is detected, the PCM may restart the engine if an auto-start-stop event is already in progress. During an auto-start-stop event the engine shuts down automatically after vehicle speed is zero. As the engine begins shutting down, there is an initial battery voltage drop due to the engine shutting off and the alternator no longer providing output current.

 

Once the engine is no longer spinning, the electrical system is fully supported by the vehicle battery. The electrical load present in the engine off phase of the auto-start-stop event causes a gradual decline in battery voltage. This gradual decline of battery voltage is the second voltage transition. The third voltage transition occurs during the engine restart. The system voltage drops, followed by the system voltage increasing to the regulation voltage point determined by the alternator output.

 

Prior to the engine restart, the PCM sends a low-side drive command to the the low voltage Direct Current/Direct Current (DC/DC) converter. The low voltage Direct Current/Direct Current (DC/DC) converter is switched into Boost mode to stabilize/boost its output until the engine has started and system voltage regulation is established by the alternator. The converter provides the stabilized or boost output voltage until one of the following occurs:

• Boost time exceeds 5 seconds
• System input voltage exceeds targeted output

The Direct Current/Direct Current (DC/DC) converter control module has full bypass or stand-by mode functionality within an input of 6V-16V. The Direct Current/Direct Current (DC/DC) converter control module must be able to provide the boosted voltage with a minimum 6V power net input voltage. If the supply voltage goes outside the voltage range, the Direct Current/Direct Current (DC/DC) converter control module recovers without user intervention when the supply voltage returns to the normal operating range. The Direct Current/Direct Current (DC/DC) converter control module determines the stabilized output voltage to be targeted by continuously measuring the Direct Current/Direct Current (DC/DC) converter control module input voltage. Prior to the restart event, the Direct Current/Direct Current (DC/DC) converter control module receives the RE-CRANK signal and sets the boosted output voltage target to be equivalent to the measured input voltage. This makes sure the output voltage to the supported loads does not change.

 

Malfunction of the system does not lead to non-function of other vehicle systems. The system enters bypass mode if:

• a thermal overload condition exists.
• there is a Direct Current/Direct Current (DC/DC) converter control module failure.
• the output voltage is more than 1V below input voltage and voltage boost is not available.

The Direct Current/Direct Current (DC/DC) converter control module self-protects against overheating and self-recovers without user interaction after an overheating event and is internally protected from short-circuits.

 

Component Description

The Direct Current/Direct Current (DC/DC) converter control module is connected in series between the high current fuse box and a select number of non-safety electrical loads. The majority of the loads are fused through the BCM and remaining loads are not fused and are switched on by a smart transistor located internal to the Direct Current/Direct Current (DC/DC) converter control module. The smart transistor acts as a fuse and shuts off power in the event of a short to ground. The Direct Current/Direct Current (DC/DC) converter control module has a dedicated body ground and incorporates a hardwired signal circuit from the PCM which notifies the Direct Current/Direct Current (DC/DC) converter control module prior to the engine cranking during an auto-start event.

 

Good luck!

[ben senise]

the real solution is to take back control and install this:

 

https://www.autostopeliminator.com/collections/ford/products/2021-ford-edge-autostop-eliminator

 

no affiliation. i have one and am 100% happy with it. when my engine stops for 1 second every time i stop at a stop sign when leaving my home and the temps are near freezing, i simply cannot believe that this is beneficial for the engine or the environment. sure, sitting at a red light for a few minutes i understand but then i can manually engage this feature.

[STBEAST]

Kudos to ben. Auto start stop is worse on an engine than stop and go traffic.  What a great suggestion. Thanks for the info!

[1004ron]

I'm surprised that the Auto Stop Start can't be disabled with Forscan - soon after we bought a BMW X5 for my wife I used Bimmercode ($50 app) to code the ASS default to OFF.

 

Edit:

If it can be done on the F150 it should be possible on the Edge.

 

Edited July 14 by 1004ron

[Wubster100]

I though the auto start stop is disabled in FORScan by disabling the BMS.

[GTEyes]

A little more on this issue. Noticed this morning that the fans for the ventilated seats were surging (making more then less noise). Sounds like something is going on with the part. I will have to get it looked at next service.