CANBus : HVAC Module (733)

All Jaguar I-Pace related discussions
dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

CANBus : HVAC Module (733)

Post by dernotte » Sun Feb 07, 2021 8:20 pm

In the HVAC Module we should find at least

- Front Evaporator Temperature Sensor
- Rear Evaporator Temperature Sensor
- Duct Air Temperature Sensor
- In Car Temperature Sensor
- Compressor Solenoid Sensor
- Compressor Clutch Sensor
- The windshield washer jet heaters
- The temperature control for the front and rear seats
- High Voltage (HV) interior heater.
Using the Jaguar Land Rover approved diagnostic equipment, check live data signal - Evaporator Temperature (0x995A). Check if the evaporator temperature is as expected when using the "MAX-AC" function. From static to operating the expected temperature is 2°C.
Using the Jaguar Land Rover approved diagnostic equipment, check the heater core temperature is as expected when in operation. The expected temperature is 80-100°C from static to full operation

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Sun Feb 07, 2021 8:54 pm

According to this diagram, there is 8 duct air temperature sensor (number #5).
I don't have the 4 zones climat option , only the 2 zones, so I am not sure I can measure rear temperature.

Capture d’écran, le 2021-02-07 à 15.51.30.png

Capture d’écran, le 2021-02-07 à 15.51.51.png

temperature of of driver seat and passenger seat , when using the seat heater can probably be found in the DSM (744) and PSM (7A3) module.

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Sun Feb 07, 2021 9:26 pm

So we need to find 8 temperatures sensors.
9854, 9855, 9856, 9857, and 4839, 9805, 988D, 9990.

Some are affected by smart control (passenger side) : 9857, 9805, some are not (driver side) : 9856, 9990.
Some have lower value than the other, so I guess those are the sensor on the floor (see diagram), and higher values are the sensors near the infotainment screen .

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Mon Feb 15, 2021 4:45 am

First impression is not always the good one. I don't think that PID 99BF is the blower RPM. I made another test today, and this one goes from 0 to 3500, and then 7000, and stayed at 7000 during all the test, even if the blower went up and down depending on the condition of my test. I don't know if we can say that it is the power for the HV coolant heater, which is a 7Kw component, but why does it not fluctuate once the temperature is stabilize in the car, and why reporting KW in HVAC when we have access to Volt and Amp ? is it Max power for heater ?
995A is the evaporator temperature (from Jag doc)
99B1 is the Volt for the HV coolant heater
9805 is a good candidate (A/10) for current on heater. If we multiply 9805 by 99b1, it reaches almost 7000 in the worst condition (max heat), and it never goes beyond 7000.
981C is the A/C power supply (from Jag doc), but this value is around 200-220, and is perfectly 1/2 of 99B1, which is the Volt available from HV battery.
9854, 9855, 9856, 9857 are the 4 front duct temperature sensors (left, center left, center right, right, not in this order).
The heater core is supposed to have a operation temperature between 80 and 100c. 99AD fits with this definition.
Last edited by dernotte on Mon Feb 15, 2021 4:07 pm, edited 1 time in total.

Maxwell_400
Posts: 380
Joined: Mon Oct 14, 2019 10:09 am
Location: Norway

Re: CANBus : HVAC Module (733)

Post by Maxwell_400 » Mon Feb 15, 2021 7:52 am

Ouch, this car is loaded with sensors! It will be a nightmare when they start to fail but this is in common with all new modern cars.

But great findings! My brain is overloaded with information.
I-Pace SE++, MY20, 18" summer & winter, no panoroof, towbar, spare wheel, 20C, TCU 19.2, BECS: BP-AAE-BC-AC-BE

Maxwell_400
Posts: 380
Joined: Mon Oct 14, 2019 10:09 am
Location: Norway

Re: CANBus : HVAC Module (733)

Post by Maxwell_400 » Mon Feb 15, 2021 7:37 pm

dernotte wrote:
Mon Feb 15, 2021 4:45 am
9805 is a good candidate (A/10) for current on heater. If we multiply 9805 by 99b1, it reaches almost 7000 in the worst condition (max heat), and it never
No, I do not think so, it is only dependent of the blower setting, maybe it is the 12 volt blower current.
I-Pace SE++, MY20, 18" summer & winter, no panoroof, towbar, spare wheel, 20C, TCU 19.2, BECS: BP-AAE-BC-AC-BE

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Wed Feb 17, 2021 4:42 am

I ran some more tests on temperature with HVAC module. I can confirm that 9854, 9855, 9856, 9857 are air temperature coming from the duct (about 45c when you request 20c in the cabin). I used my thermal camera on the dash vents, and confirm that (A/2)-40 on those PID matches the real temperature I read on the thermal camera. I focused on the 4 vents in the dash, and forgot to monitor the windshield vent, and I was not really able to get the temperature from the foot vents. I did not monitor the rear vents neither. So more work for tomorrow. I can clearly see those PID changing when I set the air on the foor, on the heat, auto, etc...

PID 98A4, 98A5, 98A7, 98A8 seems a temperature with (A-40). The 98A7 and 98A8 raised quickly when I set the air to blow on the foot. Maybe they are cabin temperature in the foot zone.

Maxwell_400
Posts: 380
Joined: Mon Oct 14, 2019 10:09 am
Location: Norway

Re: CANBus : HVAC Module (733)

Post by Maxwell_400 » Wed Feb 17, 2021 8:24 am

dernotte wrote:
Wed Feb 17, 2021 4:42 am
I ran some more tests on temperature with HVAC module. I can confirm that 9854, 9855, 9856, 9857 are air temperature coming from the duct (about 45c when you request 20c in the cabin). I used my thermal camera on the dash vents, and confirm that (A/2)-40 on those PID matches the real temperature I read on the thermal camera. I focused on the 4 vents in the dash, and forgot to monitor the windshield vent, and I was not really able to get the temperature from the foot vents. I did not monitor the rear vents neither. So more work for tomorrow. I can clearly see those PID changing when I set the air on the foor, on the heat, auto, etc...

PID 98A4, 98A5, 98A7, 98A8 seems a temperature with (A-40). The 98A7 and 98A8 raised quickly when I set the air to blow on the foot. Maybe they are cabin temperature in the foot zone.
Yes, I too looked at 9854, 9855, 9856, 9857 and can confirm your findings. I do not think we will find a current for the heater, my guess is it is controlled by a pwm and power is (HV battery) squared times pwm divided on Rptc.
I-Pace SE++, MY20, 18" summer & winter, no panoroof, towbar, spare wheel, 20C, TCU 19.2, BECS: BP-AAE-BC-AC-BE

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Wed Feb 17, 2021 4:05 pm

It seems like we have many "motors" to control.... Nothing could go wrong with this car... :-)

Capture d’écran, le 2021-02-17 à 11.03.31.png

Capture d’écran, le 2021-02-17 à 11.03.41.png

Capture d’écran, le 2021-02-17 à 11.03.48.png

Last edited by dernotte on Wed Feb 17, 2021 4:15 pm, edited 1 time in total.

dernotte
Posts: 304
Joined: Tue Dec 24, 2019 2:34 pm
Location: Montreal, QC, Canada

Re: CANBus : HVAC Module (733)

Post by dernotte » Wed Feb 17, 2021 4:14 pm

Maxwell_400 wrote:
Wed Feb 17, 2021 8:24 am

Yes, I too looked at 9854, 9855, 9856, 9857 and can confirm your findings. I do not think we will find a current for the heater, my guess is it is controlled by a pwm and power is (HV battery) squared times pwm divided on Rptc.
from Jaguar doc :
The speed of the blower is controlled by a Pulse Width Modulation (PWM) signal from the HVAC Control Module to the blower control module. The HVAC blower speed requests depend on inputs from the Integrated Control Panel (ICP) and the Rear Integrated Control Panel (RICP) (if equipped).

The blower has a 3 pin connector for the climate control assembly wiring harness. The 3 pin connector has the following electrical connections:
- A power supply from a relay in the left Front Junction Box (FJB).
- A PWM signal from the HVAC.
- A ground connection.

Post Reply