SOC-Meter (R1) User Manual and Guide

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

garygid

Well-known member
Joined
Apr 21, 2010
Messages
12,469
Location
Laguna Hills, Orange Co, CA
I hope to get a User Manual for SOC-Meter (R1) written
and posted on my web site:
http://www.wwwsite.com/puzzles/socmeter/

However, that ".pdf" has not yet been written.
So, in an attempt to be useful, I will get started here.

NOTE: This is now a work-in-progress, and there are many omissions
and there might even be some errors!!

Corrections and Suggestions welcome, please post below.

Contents:
1. First Use
2. Switch Functions
3. User Input
4. Advanced Uses
 
1. First Use

A. Connection:

The OBD cable's male plug is plugged into a mating female OBD socket (connector) that is located about 3 inches to the left of the LEAF's steering column, and about 4 or 5 inches forward "under" the dash ... above the driver's left shin.

Normally, you would follow the Test Procedure at the first-use plugging-in, to minimize the real possibility of damage to the car.

After that, plug in/out will probably be infrequent, except when testing a friend's car, or removing the SOC-Meter before visiting a Dealer for Service.

B. Initial Test (First Time Use):

You should follow the Test Procedure (see pdf at my web site) if the SOC-Meter has not been tested (or if it has been opened, dropped, modified, ... etc.), or if you are not sure.

WARNING: A short in anything connected to a car's OBD connector might disable/damage the car.

C. Display Baud Rate Setting

1. If the SOC-Meter was tested and configured properly when it was built, this setting has already been done. However, if the display has been replaced with a new unit (perhaps a different color), its default 9600 baud rate will show mostly "strange characters", and forcing (setting) the display's baud-rate to 57,600 will be necessary.

2. Setting Display Baud Rate at Power-On:
With the SOC-Meter connected to the LEAF's OBD port (to provide nominal 12v power),
a. set the Power Switch toggle to "straight out" (not Up, not Down) to turn the meter off.
b. Holding BOTH the Red and the Black push-buttons down,
c. switch the Power Switch UP (to Always-On) and wait for 3 seconds, and
d. then release both push-buttons.
e. The SOC-Meter should set the display's baud rate, display the meter's firmware number (like "F1.07"), and begin normal operation.

D. SOC-Meter Default Configuration:

1. Power Switch in Auto-ON mode (usually the toggle lever is Down). In this mode, the SOC meter should come "alive" when the LEAF is turned ON (as in Ready to drive), or when the LEAF is in ACC-2 Mode (2nd press of the car's ON button with foot NOT on the brake pedal).

2. CAN-Selector is set for EV-CAN (usually the toggle lever is down). The EV-CAN buss (when active) carries the message with a 10-bit value that we call "the raw SOC value". Although this value is NOT strictly a nice linear indicator of the car's remaining usable motive power, it appears to be related, going up to around 281 when you charge to 100%, and down to roughly 50 when the Low Battery Warning (LBW) occurs, roughly 25 when the Very Low Battery Warning (VLBW) occurs, and roughly 5 when Turtle Mode (TTM) occurs.

Note: It is BEST to plan to be recharging comfortably BEFORE TTM. The remaining useful energy MIGHT NOT be as much as this "SOC" number might lead you to believe.

WARNING: It appears that the LEAF will STOP "early" if needed to protect the "lowest" battery cell-pair. Normally (I believe), the LEAF WILL stop before zero-SOC is reached.

3. In this configuration, the SOC-Meter will automatically turn OFF when the LEAF is turned OFF, to avoid drawing extra current from the 12v battery. When ON, the Meter watches for the selected CAN buss (if any) to become active, displaying "----" as it waits. Then, a 0.0 (or just 0) is displayed until the first "SOC-message" is detected. The SOX-value is displayed in one of two formats: the "raw" value, and a "percentage" (raw 281 is currently used as 100%). The default is "percentage" format.
 
2. Switch Functions

A. Power Switch:

B. CAN-Selector Switch:

This double-pole on-off-on toggle switch provides the opportunity to display values that do not appear on the EV-CAN buss.
a. "Down" should select the EV-CAN buss (the normal default)
b. "Middle" has NO CAN-buss connection, used rarely for testing
c. "Up" should select the Car-CAN buss

The LEAF is unusual in that it has more than one "information" buss, and that the buss is basic CAN format instead of OBD2 format.

For example,
 
3. User Input:

1. Red Push-Button:
Will be used to select different display or operation Modes.
Each Mode usually displays a set of related values, or
selects a different operational function or feature.

2. Black Push-Button:
Pushed briefly while in a mode that displays more than one data
value, the display cycles through the available values.

3. Both Push-Buttons:
Held down for about 3 seconds at power-on, the SOC-Meter
initializes and sets the Display's baud rate to 57,600 baud.
 
4. Advanced Uses

1. Placement:

a. The "flat" area just in front of the cup holders is the intended location, since it is more shaded and not visually obstructive in any way. But it is too far from your line-of-sight while driving for frequent reference.

b. The Flat Area above the Nav Screen is near the driver's line-of-sight, but that area can easily get direct sunlight. However, this location can be useful in special circumstances.

c. During Charging (with the Power Switch "Up" to the "Always On" mode), placing the SOC-Meter on top of the dashboard, facing Forward, can be quite helpful.

2. Terminating Charging at 95%:

With a wire (pair) from a modified SOC-Meter to a mod on the J1772 input socket's wiring, we could simulate the J1772 nozzle being unplugged (interrupt the proximity connection) and stop charging at any selected SOC.

3. One-Channel CAN-message Logging:

With the addition of 2 wires (Ground and Data) coming out of the existing SOC-Meter to an RS232-to-USB adapter, most modern PCs can run our CAN-Do program, and watch, capture, and log all the messages from the Selected CAN-buss, using the EXISTING SOC-Meter firmware.
 
Back
Top