Overview
The CalAmp LMU-3640 features two physical connectors:
1. VBUS Connector — 16-pin Molex 43045-1609 For vehicle bus communication (CAN bus, J1939, K-Line, etc.)
2. I/O Connector — 24-pin Molex 43045-2406 For power supply, trip registration, digital/analog inputs and outputs
In most installations both connectors are used. However, depending on the required functionality, installations using only the VBUS connector are also possible.
When to Use Which Connector?
Purpose | Connector |
CAN bus data readout (J1939) | VBUS |
Power via CAN bus activity |
|
Trip registration (ignition on/off) | I/O |
Digital inputs (e.g. PTO, door) | I/O |
Analog inputs (e.g. fuel level) | I/O |
Power via direct battery cable | I/O |
Installation Profiles
Depending on the desired functionality, three basic installation profiles apply:
Profile A — Location + CAN Bus Monitoring Only
Only the VBUS connector is connected. The unit draws power from CAN bus activity on the vehicle. Ignition-based trip registration is not available, but activity can be derived from CAN bus signals (e.g. RPM > 0, vehicle speed).
Suitable for: machines with limited cable accessibility, minimal installation requirements, or where only basic monitoring is needed.
Profile B — Full Installation (Recommended)
Both connectors are connected. Power via direct battery cable, trip registration via ignition switch, CAN bus data via VBUS connector.
Suitable for: standard fleet management installations requiring complete data coverage.
Profile C — I/O Only (No CAN Bus)
Only the I/O connector is connected. Power and trip registration active, but no CAN bus data. Limited to GPS location, trip timestamps and digital inputs.
Suitable for: simple assets without CAN bus (trailers, containers, older machines).
Wiring Requirements per Installation Profile
Profile A — VBUS Connector Only
All wiring runs to the VBUS connector.
Wire | VBUS Pin | Source on Machine |
CAN H | Pin 14 | Vehicle CAN H wire / Deutsch 9-pin pin C |
CAN L | Pin 6 | Vehicle CAN L wire / Deutsch 9-pin pin D |
Power (+12/24V) | Pin 8 | Vehicle CAN bus power / Deutsch 9-pin pin B |
Ground | Pin 12 or 13 | Vehicle chassis ground / Deutsch 9-pin pin A |
The unit draws power directly from the CAN bus supply. No separate power wiring to the I/O connector is required.
Profile B — VBUS + I/O Connector (Full Installation)
Wiring is split across both connectors.
VBUS connector:
Wire | VBUS Pin | Source on Machine |
CAN H | Pin 14 | Vehicle CAN H wire / Deutsch 9-pin pin C |
CAN L | Pin 6 | Vehicle CAN L wire / Deutsch 9-pin pin D |
I/O connector:
Wire | I/O Pin | Color | Source on Machine |
Power (+12/24V) | Pin 23 or 24 | Red / Orange | Direct battery or fused power supply |
Ground | Pin 9, 10, 11 or 22 | Black | Vehicle chassis ground (use one pin) |
Ignition | Pin 12 | Blue/Red | Ignition switched +12/24V |
Power, ground and ignition detection are handled entirely by the I/O connector. CAN bus data runs exclusively through the VBUS connector.
Profile B (CanClick) — VBUS + I/O Connector with CanClick
When using the CanClick accessory, the CAN bus wiring method changes. Instead of splicing into the vehicle's CAN wires, the CAN H and CAN L outputs of the VBUS connector are fed into the CanClick device, which is then clamped over the existing CAN H and CAN L lines on the machine. No cutting or splicing of vehicle wiring is required.
VBUS connector → CanClick:
Wire | VBUS Pin | Connection |
CAN H | Pin 14 | Into CanClick CAN H input — CanClick clamps over vehicle CAN H line |
CAN L | Pin 6 | Into CanClick CAN L input — CanClick clamps over vehicle CAN L line |
I/O connector:
Wire | I/O Pin | Color | Source on Machine |
Power (+12/24V) | Pin 23 or 24 | Red / Orange | Direct battery or fused power supply |
Ground | Pin 9, 10, 11 or 22 | Black | Vehicle chassis ground (use one pin) |
Ignition | Pin 12 | Blue/Red | Ignition switched +12/24V |
Note: The CanClick handles the physical interface with the vehicle's CAN bus. The LMU-3640 VBUS connector communicates with the CanClick, not directly with the vehicle wiring. This makes it the safest and least invasive installation method.
VBUS Connector — Full Pin Reference
Pin | Signal | J1939 Type IIA | J1939 Type IIB |
6 | CAN1L | D | D |
14 | CAN1H | C | C |
12 | GND | NC | NC |
13 | GND | A | A |
8 | Vcc In | B | B |
I/O Connector — Full Pin Reference
Pin | Signal | Color |
1 | Input 1 | Blue |
2 | Input 2 | Blue/Orange |
3 | Input 3 | Violet |
4 | Input 4 | Grey |
5 | ADC-1 | Pink |
6 | ADC-2 | Black/Red |
7 | AUX1 TX | Brown/Blue |
8 | AUX1 RX | Brown/Green |
9 | GND | Black |
10 | GND | Black |
11 | GND | Black |
12 | VIN SW | Blue/Red |
13 | Input 0 | White |
14 | VCC 3V3 AUX1 | Brown/Orange |
15 | VCC 3V3 AUX2 | Yellow/Orange |
16 | 1BB T DATA | Green/Black |
17 | AUX2 RX | Yellow/Green |
18 | AUX2 TX | Yellow/Blue |
19 | OUT 0 | Green |
20 | OUT 1 | Brown |
21 | OUT 2 | Yellow |
22 | GND | Black |
23 | VIN 1 | Red |
24 | VIN 2 | Orange |
CAN Bus Connection Methods
Method 1: Direct Wire Connection
CAN H (pin 14) and CAN L (pin 6) of the VBUS connector are connected directly to the existing CAN H and CAN L wires in the vehicle. This requires tapping into or splicing the existing wiring.
Method 2: CanClick by CangoMobility (recommended)
The CanClick is a passive accessory that clamps onto existing CAN bus wires without interrupting or modifying them. It passively listens to the CAN bus and forwards the data to the LMU-3640, which transmits it to the Monytr platform.
Advantages of the CanClick:
No splicing or soldering of existing wiring
Non-invasive — original wiring remains fully intact
Faster and safer installation
Reduced risk of errors or damage to the vehicle