Interesting Article on the Connection Between Wiring Harness Tech and ICE vs EV

[Dave9]

^ But it's still only a temporary shortage, while batteries and ICs are still a shortage as well, the former for years to come if there is ever enough without a substantially different battery tech. European ICE vehicle sales decrease, does not mean that EV production can increase to take up the slack. It as likely means an increase in ICE vehicle sales once production is at full capacity again. Supply vs demand.

 

[JeffKeryk]

^ But it's still only a temporary shortage, while batteries and ICs are still a shortage as well, the former for years to come if there is ever enough without a substantially different battery tech. European ICE vehicle sales decrease, does not mean that EV production can increase to take up the slack. It as likely means an increase in ICE vehicle sales once production is at full capacity again. Supply vs demand.

The supply demand relationship changes as viable demand alternatives emerge. In high demand products, competitors will enter the market by building alternatives. The curve is always affected by consumer preference, if choice exists.

An example is, if a certain vehicle is in short supply and EVs are are available, if customers do not want an EV (for whatever reason) the demand supply relationship is not affected nearly as much.

 

[JHZR2]

Here’s a better read perhaps…

https://www.techbriefs.com/component/content/article/tb/stories/blog/45485

 

[JeffKeryk]

I think the title was pretty lame and misleading. If there is a better way to develop and manufacture wiring harnesses, the type of drivetrain makes no difference. This is not an EV vs ICE arguement, but was presented this way.

 

[nthach]

The majority of wiring harnesses are made by Japanese firms - Yazaki or Sumitomo, but a French company - Fareucia and Aptiv, formerly the electronics side of Delphi is involved too. The connectors come from all over the world but mainly American(TE AMP, Molex, Amphenol and ITT Cannon) or Japanese(JAE, Sumitomo, Furukawa, JST, Hirose). They are labor intensive and are usually made in China, the Philippines or Vietnam.

With EVs, it’s possible to have the data side on just a pair of wires or implement star-based topologies like an Ethernet network. Cars will only be loaded down with more data buses - CAN, FlexRay, MOST, A2B, etc. Many of those buses can work over twisted pair, MOST can be over optical cable, A2B which is Ford’s new audio bus is over USB. For ICEs, there’s lots of parallel wiring and data/discrete signals/power needing to go around.

A similar thing happened to the truck/bus/RV industry - multiplexed electrical systems using ladder logic and modules throughout the chassis/body. Instead of miles of wiring and relays, all you need is power and data bus(CAN or serial) between the modules and the main controller, the modules have fused input/outputs and solid state/optoelectronic relays on board with software-defined switching outlooks.

 

[brianl703]

With EVs, it’s possible to have the data side on just a pair of wires or implement star-based topologies like an Ethernet network.

The same is done with ICE cars and has been for over a decade now.

 

[nthach]

The same is done with ICE cars and has been for over a decade now.

But it’s a mess on how it’s done right now. There isn’t a “standard” bus or connector for it - in computing the IEEE and the consortiums for every connectivity standard set specs on how things should be implemented. CAN/FlexRay/MOST are mostly standard but the Japanese and GM have been renegades with their own specs(GM-LAN/LIN, Toyota’s BEAN, the 4 implementations of IEBus from NEC/Renesas that Toyota, Honda, Nissan and Pioneer use) and even CAN is fragmented, with Honda using SW-CAN and most recently they and Ford are using “low-speed” MS-CAN and “high-speed” CAN in the same car.

IMO, the hope with BEV/FCEV is simplified wiring, as the car makers will have to think like the computer makers are. The data bus connector and wiring standards for heavy-duty have been more defined than automotive.

 

[JHZR2]

With EVs, it’s possible to have the data side on just a pair of wires or implement star-based topologies like an Ethernet network. Cars will only be loaded down with more data buses - CAN, FlexRay, MOST, A2B, etc. Many of those buses can work over twisted pair, MOST can be over optical cable, A2B which is Ford’s new audio bus is over USB. For ICEs, there’s lots of parallel wiring and data/discrete signals/power needing to go around.

ICE already use data busses for various things. My 93 Mercedes does, my 2003 Saab did, etc. Protocols and implementation isn’t the issue. The practice is established.

For the EV, how do you think the cells are monitored and balanced? Every single cell group has leads on it from the cell group to the BMS, for voltage monitoring and resistive balancing. The thermistors (better made batteries have more, some have less) all have wiring. So do all the ancillary parts like cooling pumps, contactors, ground fault detection, etc. lots of discrete items just like an ICE. Plus the main conductors which are substantial.

Some of this is truncated at the BMS, which could have a data stream going to/from it, but the battery still has a rats nest of wiring inside it. Worse than any engine…

And the EV isn’t absolved of all the other wiring. ABS sensors, switches, controls, speakers, cooling system elements, hvac, etc. Its always a laugh when folks try to claim a reliability advantage for EVs. Motor drives are notoriously unreliable. All the rest of the parts like suspensions, infotainment, HVAC, etc. all will have the same kinds of issues. Not to mention paint, rubber parts, etc. While harnesses have been known to be a reliability issue (ask 90s Mercedes owners), it’s by far not the major repair anyone sees.

 

[brianl703]

While harnesses have been known to be a reliability issue (ask 90s Mercedes owners), it’s by far not the major repair anyone sees.

Let me guess, 90s Mercedes have PVC-insulated wire underhood and it starts getting brittle as the plasticizers migrate out of the insulation due to the heat...

Ford had the same problem on the Contour/Mystique and probably the Mondeo too.

 

[brianl703]

But it’s a mess on how it’s done right now. There isn’t a “standard” bus or connector for it

And what problems does that actually cause? Do automakers really care that a module from a Ford car won't talk on a Toyota databus?

 

[JeffKeryk]

And what problems does that actually cause? Do automakers really care that a module from a Ford car won't talk on a Toyota databus?

Cost. I have worked on a tons of manufacturing cost analysis. Standards make our life easy. Part commonality saves tons of money, engineering costs, simplifies BOMs and enables part reusability. I imagine you know procurement is the biggest cost and #1 headache in manufacturing.

 

[E365]

GM Ultium uses wireless BMS. Claims up-to 90% reduction in wiring inside the packs.

 

[nthach]

And what problems does that actually cause? Do automakers really care that a module from a Ford car won't talk on a Toyota databus?

One, it makes life easier for techs, especially the aftermarket - but also flat-rate dealer techs who don’t get much “training” besides an self-paced online course by the OEM. Two, since cars are slowly becoming a computer on wheels and as much as the OEMs hate R2R and aftermarket accessories, it may open up an avenue for the aftermarket and enthusiasts to tweak their cars. Everything will be software defined, eventually.

 

[JHZR2]

GM Ultium uses wireless BMS. Claims up-to 90% reduction in wiring inside the packs.

Yes, some are going to that. But you still need leads to sense, and particularly to balance.

 

[brianl703]

One, it makes life easier for techs, especially the aftermarket - but also flat-rate dealer techs who don’t get much “training” besides an self-paced online course by the OEM. Two, since cars are slowly becoming a computer on wheels and as much as the OEMs hate R2R and aftermarket accessories, it may open up an avenue for the aftermarket and enthusiasts to tweak their cars. Everything will be software defined, eventually.

Neither of those seem to be things that automakers care about.

 

[JeffKeryk]

Neither of those seem to be things that automakers care about.

Choosing bad design over good design? That's a recipe for failure.
Why would anyone do that?

 

[brianl703]

Choosing bad design over good design? That's a recipe for failure.
Why would anyone do that?

In the case of the aftermarket, making things easy for them means dealerships losing business.