Tesla Model S/X Coolant Pump
Overview
Both the Model S and X use a very capable (but curiously unbranded) coolant pump. Internet research seems to indicate it may be made by VariMax[1], though there are so many Tesla part numbers it's hard to say which actual model it is. The Nissan Leaf also uses this pump.[2]
In ICE circles, this pump is commonly used in high performance intercooler systems, so Lingenfelter Performance Engineering has compiled a fairly thorough (though questionably formatted) datasheet on the pump. Another fairly thorough overview can be found within the EV Create overview of the Tesla cooling system[3].
Specs
Some basic specs for the pump are as follows[1]:
- Target flow rate 720 LPH @ 70 kPa
- Inlet / Outlet connection: 19 MM Barb
- Motor syle: Brushless
- Operating voltage: 8-16 VDC
- Maximum amp draw: 7.3 Amp
Control
The pump can be controlled using PWM. The PWM voltage is 5V and the frequency is a rather unusual 2Hz. The pump speed can be controlled from ~750RPM at 20% duty cycle to ~5000RPM at 80% duty cycle.
Wiring
Connector
The pump has a single 4-pin plug which contains both the power and control signals. The plug itself is Sumitomo “RS” series:
- socket (female): 6189-7757
- retainer: 6918-1599
- pins (female): 8240-0263 (0.3-0.5mm2/24-20ga), 8240-0264 (0.85-1.25mm2/20-18ga), 8240-0265 (2.0mm2/16-14ga)
- seals (cable OD): 7165-0474 (1.0-1.4mm), 7165-0473 (1.5-1.9), 7165-0472 (2.0-2.4), 7165-0471 (2.5-2.9/18ga)
- RS04FG is also a commonly available connector that fits.[4]
As Sumitomo connectors aren't widely available, a better source for this connector is Aliexpress where is is often sold as a complete connector kit.
Alternatively, there's a common Nissan/Subaru O2 sensor connector, with flying leads furnished, that is a perfect fit[5].
Pinout
Issues
The pump has a flow sensor, so it will not run empty/dry. Even when primed, the pump takes a moment to spool up.
Annoyingly, the bearing is integral to the impeller, so if you have a noisy pump there is no way to replace just the worn part.
References
- ↑ 1.0 1.1 https://www.diyelectriccar.com/threads/the-teslorean.170770/post-856074
- ↑ https://openinverter.org/forum/viewtopic.php?t=2906
- ↑ https://www.evcreate.com/using-tesla-thermal-management-system-parts/#tesla-pump
- ↑ https://openinverter.org/forum/viewtopic.php?p=46064#p46064
- ↑ https://openinverter.org/forum/viewtopic.php?p=46064#p46064