So I went a number of weeks without driving my car as I was on vacation and with the cold weather the battery was dead. Jump starting this thing proved impossible. It looks like from the web that there is a specific place to put the positive cable on the ES 350, rather than simply to the positive post on the dead battery. I could not make head nor tail of the descriptions of where to actually put the positive clamp. In any event, I have Lexus roadside assistance coming to help me with the damn thing

 

I just put the jump start directly on the battery terminals, the same as when I use a battery charger to top it up…no problem. You might be thinking of the hybrid which likely has a specific procedure.

 

Red cable to positive on the battery and black to negative post.

 

I was always taught that - way back in the day - to just attach everything to both batteries, but for some time auto maker recommend NOT doing that, instead attaching the negative cable to a grounding point in the engine bay of the car with the dead battery. This is for safety (possible presence of hydrogen leak from the dead battery getting ignited by a spark if one occurs) and to protect electronic components in the car (ECU’s) and sensors which can be damaged by the jump start directly to the battery.

Connection Order:

Connect the Red clamp to the positive (+) terminal of the dead Lexus battery.
Connect the other Red clamp to the positive (+) terminal of the donor battery.
Connect the Black clamp to the negative (-) terminal of the donor battery.
Connect the other Black clamp to a solid, unpainted metal point on the dead car's engine, away from the battery and fuel components.

 

You're correct and this is the best way. However the OP seems to be unfamiliar with this procedure.

 

dead car: i always do red on pos terminal on battery, and negative on shock tower, engine hook etc.

donor car: both clamps on battery terminal. the donor car should have the engine running and engine revs up a bit.

the way ive always done it and it has worked. one time i used crappy thin cables and they started smoking after trying to jump my bmw. too thin. always buy thick cables and pay the extra bucks.

 

If you don't already have one, suggest you get one of the various for-sale smart battery charger/maintainer/tender products. Smart in that it will charge a battery up to optimal charge voltage for the battery type and then go into a charge maintenance mode where it monitors the voltage level and only applies charging current when needed to maintain that voltage level. That will keep your battery fully charged up without having to worry about damaging the battery from overcharging.

Then, whenever you anticipate not driving your ES enough to keep its battery in a fully charged state, hook it up to the smart battery charger/maintainer/tender and you won't have to worry about finding your ES has a discharged battery. (It won't eliminate a battery going bad; however, some of the smart battery charger/maintainer/tender offerings include a "battery health" feature which will inform you if a battery is still good or has degraded to a point where it needs to be replaced.)

Some of the smart battery charger/maintainer/tender offerings also have available accessories like ring terminal battery connections with weather-proof fused quick (dis)connectors and long extension charging cables. The ring terminal connections are a semi-permanent charging cable connection that allows you to avoid the continual hassle of connecting and disconnecting battery terminal cable clamps. Some ring terminal kits have long enough pigtails that allow for the quick-connect connector to be placed where you can connect/disconnect the battery charger/maintainer/tender without having to open the ES's hood.


As a resident of the Great White North, you may want to ask a Lexus Canada dealer if they have a battery maintainer kit for the ES. At one time, I thought I saw Lexus Canada offering a quick-connect battery maintainer kit to go along with their ES quick-connect block heater kit but now I only see the block heater kit on the Lexus Canada ES accessories listing.
The 2023 Lexus ES350 Owner's Manual on page 375 (under the "If the battery is discharged" section) has an illustration for the ES 350's 2GR-FKS engine on where/how to connect jump-starting cables. That page also has the written connection instructions that ATL350 posted.

If you didn't get copies of the ES manual set when you purchased your used ES, you can download PDF copies from Lexus Canada's Owner's Manuals website or from US Lexus's My Lexus/resources' MANUALS & RESOURCES website. (It doesn't make any difference since both are the same version.) For your convenience, Lexus Canada ES 350 Owner's Manual (64.2MB) is the direct link to download a PDF copy of the Owner's manual for your ES.

 

And for safety to prevent arcing always connect Neg last and when done disconnect Neg 1st.

 

On the ES and a few other Lexus vehicle model types don't use anything around the driver's side shock tower to avoid frying the engine ECU. See ESh's Attention: jump starting may fry the ECU! post #1 and the Lexus TSB L-TT-0336-24, November 06, 2024, "DTC U010087 & No Start / Replaced Engine ECU AfterJump Starting" for details.

 

OM for my 2020 350 says connect to “positive battery terminal” and “solid, stationary, unpainted metallic point away from battery and any moving parts.” No mention of the fuse box terminal or concern about ECU.

 

And always tip your roadside rescuer.

 

From all versions of this generation's ES350 Owner's Manuals:
The "as shown in the illustration" you didn't include; the illustration shows on the ES being jump started connecting the negative end clamp to a location on the side of the engine opposite the side where the battery is located. So, if one correctly follows the Owner's Manual instructions on jump starting, you won't be connecting the negative end clamp anywhere on the driver's side of the vehicle, avoiding any possible danger of frying the engine ECU, and thus not requiring any warning about areas/locations not to use for negative clamp connection points so as not to fry the engine ECU.

That said, you won't be the first nor the last to gloss over and not strictly follow the "as shown in the illustration" instruction. Also, given the breadth of Lexus model types covered by the TSB, I wouldn't rule out the Lexus design engineering department having a few blind spots and mistaken assumptions about vehicle jump starting practices by end users in the real world.

 

I did not gloss over anything. No mention of forbidden bolts for negative or anything other than battery terminal for positive. These were your main points. Also no mention of ECU.

Yeah, always depend on forum posters to fill in blind spots of Lexus design engineers.

 

Geez guys, this ain't brain surgery...

 

And make sure the chrome bumpers don’t touch 😂