Honda EU7000IS "Data Link Connector"

This project's goal is to understand the Honda EU7000IS "DLC" "Data Link Connector". The DLC connector is used for diagnostics with Honda's "Dr.H" Diagnostics tool.

Using Honda's Diagnostics tool enables you to query the Generators Serial Number and stream real time sensors for the following

Engine Run Time
Engine Speed
Battery Voltage
Cylinder Head Temperature
Ignition Timing
Air Temperature
Barometric Pressure
Fuel Injection Time
Throttle Position
Total Output Power
Starter Count
O2 Sensor Voltage
For both the Master and Slave Inverter:
- Status
- Output Voltage
- Amperage
- Temperature
- Eco Mode

Gaining real time access to the above sensor information could enable some interesting custom integrations into smart home or power systems.

Disclaimer

I am not associated with Honda in any way. The EU7000IS generator model has variance between regions. This research was done with a Canadian 2021 model. Your mileage may vary. Some of the information provided could be incorrect.

Physical layer

The DLC connector is uses a Sumitomo HM 6187-4441 Connector

It has 4 pins.

Pin	Description	Color
1	TX	Blue/Red
2	GND	Green
3	VBatt	Brown/White
4	RX	Blue/Yellow

The RX/TX Pins

Are standard UART Serial
Use 5v Logic Levels
Use 9600 Baud with 8 bits no parity 1 stop bit.
Are both inverted with Idle state low and Active state high.

Messages are sent and received as ASCII Terminal Messages.

A valid TX message (hex) would be:

01 43 42 30 30 30 30 30 31 04

The first byte of each message is 0x01 (Terminal Start of Frame) The last byte of each message is 0x04 (Terminal End of Transmission)

The ascii message above reads as

CB000001

Understand the Messages

I have found the following unique TX messages.

BA00FF03
BC000001
BD000006
BE000007
CA000002
CB000001
CB100000
CB200003
CB300002

This is my understanding of the following TX messages and their responses.

Sensors

CBxx is used to query data. xx appears to be the address of the data request. Valid addresses appear to be

ECU information Part 1

CB000001 is used to query general engine information from the ECU.

In the following examples the top describes the byte number followed by hex response examples.

Example Reply

0  1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18
CB 00 00 00 18 09 6F 83 00 60 2F 01 03 01 F2 00 06 7E 0B
CB 00 00 00 18 09 64 80 00 64 2F 01 03 01 F2 00 06 7E 7E
      ** runtime in days? Have no evidence yet.
         ** runtime in hours
            ** runtime in minutes.
               ** ** engine RPM
                     ** Battery voltage * 0.1 
                        ** ** Cylinder head C -50
                              ** Ignition Timing Degrees -10
                                                   ** Output voltage?

ECU information Part 2

CB300002

Example Reply

0  1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18
CB 30 3C 63 01 81 0D 90 02 1A 00 10 0A 00 00 00 00 00 00
CB 30 3C 63 01 8F 0D 90 02 1A 00 10 0A 00 00 00 00 00 77
** ** * never any change
       * C or D????
         ** Barometric Pressure
            ** ** Fuel injection time * 0x01 in ms
                  ** Throttle position
                        ** ** Output power in VA ????
                              ** ** Starting count
                                    ** O2 sensor * 0.1 volts

Master Inverter

CB100000

All zeros when the gen is not running

Example Reply.

0  1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18
CB 10 00 07 2F 00 00 03 03 00 00 00 00 00 00 00 06 7E 07
CB 10 00 06 2F 00 00 03 03 00 00 00 00 00 00 00 06 7E 06
CB 10 00 14 2F 00 00 03 03 00 00 17 00 00 00 00 06 7E 03
         ** Output amperage * 0.1
            ** Temperature C -40
                        ** Eco mode. 2 == On 3 == Off
                              ** ** Output watts * 10
                                                   ** Output voltage

Slave Inverter

CB200003

All zeros when the gen is not running.

0  1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18
CB 20 00 18 31 00 1E 00 00 00 00 00 00 00 00 00 00 00 7C
CB 20 00 19 2F 00 21 00 00 00 00 00 00 00 00 00 00 00 7C
CB 20 00 1A 30 00 20 00 00 00 00 00 00 00 00 00 00 00 72
         ** Output amperage * 0.1
            ** Temperature C -40
               ** ** Output watts * 10

Note: All of these captures are done in 120v mode. The slave probably also reports volts when in 240v mode.

Keep Alive

BA00FF03 Occurs at the start of every connection. Also occurs frequently while idle. Probably a sort of start communication or keep alive message.

In my case it is always replied with BA000201

Other

CA000002 is a query for the generators Serial Number.

blaisejarrett/Honda-Gen-PGM-FI-Protocol