A-4 Code L204 With L205 Or L206 Addressing Problem

Code L204 and L205 or L204 and L206 indicate a loss of power to an OSM address pin. When such an addressing failure exists on pin F of OSM # 5 or pin E of OSM # 6, its address becomes the same as that of OSM # 4. Therefore, when the Body Control Module (BCM) sends a command on the data line to OSM # 4, both OSM # 4 and the misaddressed OSM both respond resulting in a lighting fault. When the BCM sends a command to the misaddressed OSM, there isn't an OSM available to respond resulting in a lighting fault. The table below lists the Computer Control Driver Information Center (CCDIC) messages and symptoms of these conditions.

In addition to address problems the combination of codes L204 and L205 could also indicate a problem with the power supply circuit 1602.

NOTES ON TROUBLE TREES
1. This checks for voltage supply on circuit 1604. If voltage is present, each code must be diagnosed.
2. If the fuse is open, the circuit 1604 must be checked for a short to ground.
3. If the fuse is OK, there is an open or short to ground in the voltage supply (circuit 2) to the fuse or an open in circuit 1604.