Purpose: Test, Diagnose, and repair the J1939 connection.
Details: Chassis information is received from the J1939 network and transmitted via the 3rd Eye Gateway.
Issue: J1939 is reported as “FAIL[ ]”
If the J1939 is reported as down it means that the 3rd Eye Gateway has lost communication with the J1939 network.
Step 1. TEST: Use the window unit to determine if the J1939 network is communicating to the 3rd Eye Gateway. The yellow light at the top is the indicator for the J1939 network and will illuminate when the network is communicating to the gateway (Figure 1.1). If it is illuminated and the unit is reporting J1939 as failed contact 3rd Eye Technical support for further assistance. If the yellow J1939 light is not illuminated, proceed to Step 2.
Step 2: Locate the 3rd Eye connection point to the J1939 network, usually identifiable by the Y-splitter (Figure 2.1) connected to the chassis harness (example of Figure 2.2). Inspect all connections and make sure that the connector pins aren’t damaged. If there is any damage or disconnected harnesses, repair and reconnect. Check the J1939 harness going towards the 3rd Eye Gateway for damage. If all connections and pins look good, proceed to Step 3.
Step 3. A VOLT METER SET TO OHMS IS REQUIRED FOR THIS STEP. Disconnect the 3rd Eye gateway and check the resistance between the green and yellow wires on the splitter side. This should be 60 ohms. If the measurement is 120 ohms there is a terminating resistor missing from the circuit. Locate the missing resistor and reconnect. If the measurement is 40 ohms there is an additional resistor added to the circuit. Locate the additional resistor and remove. If the measurement is correct at 60 ohms contact 3rd Eye for additional support.