DESCRIPTION
Using this circuit, the radio receiver assembly sends power to the map light assembly, and the map light assembly sends microphone signals to the radio receiver assembly.
WIRING DIAGRAM
| *a | Telephone Microphone Assembly |
| *b | Shielded |
| *c | Map Light Assembly |
| *d | Radio Receiver Assembly |
PROCEDURE
CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY)
Disconnect the G48 radio receiver assembly connector.
Disconnect the Q16 map light assembly (telephone micro phone assembly) connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK RADIO RECEIVER ASSEMBLY
| *a | Component with harness connected (Radio Receiver Assembly) |
Remove the radio receiver assembly with its connector still connected.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE RADIO RECEIVER ASSEMBLY Click here |
| OK |
|
INSPECT MAP LIGHT ASSEMBLY
Remove the map light assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK TELEPHONE MICROPHONE ASSEMBLY Click here |
| OK |
|
CHECK MAP LIGHT ASSEMBLY
| *a | Component with harness connected (Map Light Assembly) |
Remove the map light assembly with its connector still connected.
Turn the ignition switch to ACC.
Connect an oscilloscope to terminals 4 (MCO+) and 6 (MCO-) of the map light assembly connector.
Check the waveform of the telephone microphone assembly using the oscilloscope.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| B |
|
CHECK TELEPHONE MICROPHONE ASSEMBLY
Replace the telephone microphone assembly with a new or known good one and check that the malfunction disappears.
| Result | |||
|---|---|---|---|
|
| Malfunction disappears |
|
END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE) |
| Malfunction appears |
|
CHECK MAP LIGHT ASSEMBLY
Replace the map light assembly with a new or known good one and check that the malfunction disappears.
| Result | |||
|---|---|---|---|
|
| Malfunction disappears |
|
END (MAP LIGHT ASSEMBLY IS DEFECTIVE) |
| Malfunction appears |
|
REPLACE RADIO RECEIVER ASSEMBLY Click here |
CHECK TELEPHONE MICROPHONE ASSEMBLY
Replace the telephone microphone assembly with a new or known good one and check that the malfunction disappears.
| Result | |||
|---|---|---|---|
|
| Malfunction disappears |
|
END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE) |
| Malfunction appears |
|
REPLACE MAP LIGHT ASSEMBLY Click here |