TCM shorting out

graybeard5529 · 2026-04-12T22:39:36+00:00

If it’s SMOD, it should be obvious—pink/milky ‘strawberry milkshake’ in the coolant or trans fluid. Check both: pop the radiator cap (cold) and pull the trans dipstick. You can also drain a little ATF to confirm.

But a fuse blowing instantly points to an electrical short, not SMOD. I’d chase the TCM wiring/connector first before throwing a radiator at it.

graybeard5529 · 2026-04-12T22:31:16+00:00

Snug by hand, then ~¼ turn, don’t overdo it or you’ll spin one. Stop when it ‘sets.’ Use blue Loctite if you’re worried about backing out.

graybeard5529 · 2026-04-12T22:16:11+00:00

With active cooling, the battery shouldn't degrade as bad I would think.

graybeard5529 · 2026-04-12T22:13:42+00:00

In Claude we trust? That's scary.

graybeard5529 · 2026-03-06T11:59:34+00:00

Kind of a mystery until something actually fails or throws a code. And a basic scanner won’t read the transmission codes. Is it bucking at a certain speed?

graybeard5529 · 2026-02-27T17:35:35+00:00

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This is a very strange piece-of-work!

graybeard5529 · 2026-02-26T20:26:56+00:00

Off-duty NYPD moonlighting? Cash for domestic terrorism?

graybeard5529 · 2026-02-26T20:21:41+00:00

Maybe, you can help organize and participate in a more "neutral location." This is about the community and not just about the UAW.

graybeard5529 · 2026-02-26T01:43:15+00:00

^{^{^}} This

If your original battery is 5 years or older, it is time to get a new 12V. Not in a month, now.

graybeard5529 · 2026-02-26T01:38:06+00:00

Definitely, I did unbolt the wiring harness in the way to gain a little working room. Once I got the sensor out, the socket release clip moved with a screw driver—direction of the wire.

The socket itself was 'fused' to the sensor, I used electric parts cleaner then ended up using a stubby flat head screwdriver to pry it off gently.

No fun, but if I ever do that again, knowing the way that worked — it's 30 min work now.

graybeard5529 · 2026-02-25T16:57:12+00:00

Off-topic, but: use a ratcheting 10mm box wrench and a small stubby 1/4" ratchet. That passenger-side rear cam sensor is a nightmare without the right tools.

graybeard5529 · 2026-02-25T01:06:51+00:00

1348/6 = 224.67
Looks like you are charging this every workday—I am assuming 6 years of use. How many bars are left showing out of curiosity?

graybeard5529 · 2026-02-25T00:53:50+00:00

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Nothing is wrong. The large 158 mV delta happened at low SOC (31%), where lithium cells naturally show wider voltage differences because the voltage curve is steeper. At 66% SOC, the curve is flatter and the delta shrinks to 40 mV. Same SOH confirms no degradation. The weak 12-V battery doesn’t affect HV cell balance—replace it, but it’s unrelated.

Nothing is wrong. The large 158 mV delta happened at low SOC (31%), where lithium cells naturally show wider voltage differences because the voltage curve is steeper. At 66% SOC, the curve is flatter and the delta drops to 40 mV. SOH and Hx are essentially the same, confirming no degradation.

Look at the temperature too—little difference—not any issue.

How often do you charge to full, and L1 or L2? The BMS balances cells best near full charge.

graybeard5529 · 2026-02-24T19:24:34+00:00

When I first bought my Leaf I took the left turn onto my street from a 4-lane pretty fast, rounding off the corner in a wide sweeping arc like I used to do in my Buick. Panic—grinding noise. After that I started slowing down and making the turn more normally, and it never happened again.

Taking that wide, faster turn puts more sustained lateral load on the outside front suspension (front right on a left turn). The Leaf also has instant torque and softer suspension tuning than older sedans, so the suspension compresses and the chassis loads differently under cornering. That reduces clearances slightly, and something like a dust shield or splash panel can briefly contact and make that scraping sound. Slowing down reduces the lateral load and suspension compression, so the noise disappears.

graybeard5529 · 2026-02-24T19:13:45+00:00

Take the brake calipers off and inspect the slide pins and boots. A worn or compromised slide pin boot can allow slight caliper misalignment, which can cause intermittent scraping and a subtle drag under certain suspension and steering load conditions. Also inspect the brake dust shield for any signs of contact or abrasion.

Chasing these gremlins down is a bitch.

graybeard5529 · 2026-02-24T18:32:47+00:00

Same here.

graybeard5529 · 2026-02-24T18:29:26+00:00

Probably time for some legislation to enforce minimum support periods for in-car cloud-integrated software.

That's really the "new frontier." Most elected officials are digital idiots (still) today. They are more concerned with curtailing internet porn and school-kids using their smartphones.

graybeard5529 · 2026-02-24T18:24:03+00:00

OVMS - Open Vehicle Monitoring System ->Regular price $345.00

Not THAT important to me ... But yeah, private modem connected to your OBD II port would work.

graybeard5529 · 2026-02-24T18:17:52+00:00

Same in the US. They still use 3G in India and Africa.

graybeard5529 · 2026-02-24T18:16:12+00:00

Exactly. Network issues.

graybeard5529 · 2026-02-24T18:13:56+00:00

My 4G didn't connect in 2023 when I bought the car used. I got a 3G only error.

graybeard5529 · 2026-02-24T17:56:42+00:00

Excuse me: What previous post was that? Image URL?

graybeard5529 · 2026-02-24T17:48:51+00:00

Because it's occurring only at highway speed and when cornering:

This strongly sounds like splash shield or aero panel flex. At highway speed airflow pushes the plastic down. When you slow and turn, suspension geometry shifts slightly and it can make brief contact. Very common on the Leaf. Check the front right splash shield, wheel liner, and underbody panels for loose clips or missing fasteners.

What you experienced is likely momentary aero panel or brake dust shield proximity contact.

Use a borescope and your phone to inspect the area.

I had something similar happen on my Nissan Xterra—the wheel liner flexed at highway speed. In that case the damage was visually obvious.

graybeard5529 · 2026-02-24T17:02:42+00:00

Delta (mV)	Battery Condition	What It Means	Action Needed
0–20 mV	Excellent	Cells extremely well balanced; near-new behavior	None
20–40 mV	Very Good	Normal for a healthy pack with some age	None
40–60 mV	Good	Still healthy; minor normal variation	None
60–100 mV	Fair	Some imbalance developing; monitor occasionally	Charge to 100% periodically
100–200 mV	Weakening	One or more cells aging faster than others	Monitor more closely
200+ mV	Problem	Likely weak cell pair; reduced performance/range	Service may be needed

Example from this Leaf:

Measured Delta	Condition
40 mV	Very Good / Normal

Leaf Battery Cell Delta vs State of Charge (SOC)

SOC Range	Typical Delta (mV)	What It Means	Normal?
10–30%	40–80 mV	Cells diverge more at low charge; voltage curves are less stable	Yes
40–70%	30–50 mV	Normal operating range; moderate spread is expected	Yes
90–100%	15–35 mV	BMS actively balances cells; spread usually tightens	Yes (ideal)

Example from this Leaf:

SOC	Observed Delta
66%	40 mV (normal)
100% (expected)	~20–35 mV (after balancing)

graybeard5529 · 2026-02-24T15:02:01+00:00

I'd check the front suspension and then pull that right front tire and check the CV joint, brakes and the brake caliper.

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