Under The Mach-E Hood / Frunk: motor components, electrical control hardware, and DIY maintenance point

[ClaudeMach-E]

Isn't that what is called e-Heat or something?

Sponsored

 

[Mirak]

Wow - I thought EVs were supposed to be simpler under the hood than ICEs. This doesn't look simpler. It looks more like a combination of this....

and this....

It's a littttttle disappointing that all that plastic has to be removed to access the coolant reservoir, brake fluid, and 12v. I try to avoid monkeying around under the hood but I've had to replace a few batteries.

 

[guyofthesky]

Chevy took a different approach with the Bolt. There are still a lot of similarities with the Mach E however. The Bolt clearly benefits from FWD only optimization and employs three distinct loops for cabin heat, battery and motor/electronics. The Bolt of course has one less motor to keep cool.

The Bolt uses a traditional radiator for the electronics/motor loop. It also has actuated shutters like the Mach E, but they're not visible externally. The battery loop is integrated into the AC system via a chiller to help cool the battery which adds to electric consumption to drive the compressor and condenser fan. It also has three electric pumps to move the coolant around.

It seems that Ford has engineered coolant loops that are common to all functions which means you can likely use heat generated by the components to warm the cabin, presumably reducing the need for resistance heating. That's not possible on the Bolt. The Mach E seems to have an additional pump, presumably because there's an extra motor. It's likely they're using the motors to direct the flow of coolant to where it's most needed within a common system. I don't know if there's an integrated chiller for battery cooling.

When I first saw these loops in a factory video, I also was concerned but assumed that Ford engineered a low PSI system with lower operating temperatures that would create less stress on the components leading to longer life. The above video seems to suggest however that the Mach E cooling system is engineered to support up to 21 PSI while the Bolt's operates at 5 PSI. I find this surprising given that low PSI systems have been in use in most hybrids and other EV's for years.

The Ford system to the eye looks more complicated due to the addition of RWD and routing of multiple loops into a common system. However, the system will likely draw less power from the battery to keep the battery, components and cabin comfy. It seems they've optimized the system to recapture as much heat as possible, which would likely require more routing of coolant.

Thanks for posting this! I found it very interesting. Nice work.

 

[dtbaker61]

ok.... got my MME (2/26/21) and am 'exploring' under the hood a little.... first step is to make access to the 'customer load terminals' easier for jump start and/or actual external loads. Plan is to cut 2" holes over 'terminals', and use knock-out plugs (common for electrical J boxes and service panels) for easy pop-off access when needed.

Second is I'd like to verify what the MAXIMUM continuous LV load is. I am guessing it is the max capacity of the DC-DC converter which feeds the LVB. Only info I have found is that this is 160amp x 12v(nominal) = 1920 watts, or probably more like 2000 watts at 'working voltage'

Before I proceed, I thought I'd ask if anybody had any info to the contrary regarding max continuous customer load via LVB connection points; which the main battery should *wake up* and recharge if needed during operation of external loads.

 

[SnBGC]

ok.... got my MME (2/26/21) and am 'exploring' under the hood a little.... first step is to make access to the 'customer load terminals' easier for jump start and/or actual external loads. Plan is to cut 2" holes over 'terminals', and use knock-out plugs (common for electrical J boxes and service panels) for easy pop-off access when needed.

Second is I'd like to verify what the MAXIMUM continuous LV load is. I am guessing it is the max capacity of the DC-DC converter which feeds the LVB. Only info I have found is that this is 160amp x 12v(nominal) = 1920 watts, or probably more like 2000 watts at 'working voltage'

Before I proceed, I thought I'd ask if anybody had any info to the contrary regarding max continuous customer load via LVB connection points; which the main battery should *wake up* and recharge if needed during operation of external loads.

I thought the manual said "capable of up to 160 amp" which is probably different than max continuous output. I tried to look it up but I forget where I saw that note.... ?

 

[dtbaker61]

I thought the manual said "capable of up to 160 amp" which is probably different than max continuous output. I tried to look it up but I forget where I saw that note.... ?

yeah, that's what I remember, but I couldn't remember where I read it.... I am guessing the 2000 watt limit is the 'continuous' rating that was built in to handle ALL on board loads in case people had heater, seats, steering wheel, stereo, and cabin power outlets all going at once.

I'm probably going to fuse any external loads to draw no more than 2000 watts on this basis....

 

[BradCA]

I thought it only needed minimal maintenance / hardware and that would be a coolant change every 200k miles?

There appears to be a lot in there that could and for some will fail at some point. Depressing.

I thought the engine was cooled in a cutting edge way not a standard radiator!

Ice melting from the frunk/cooler is what cools the engine.

 

[dtbaker61]

Ice melting from the frunk/cooler is what cools the engine.

not an 'engine', but a 'motor' .....