Mazda RX8 - Troubleshooting: ALC Does Not Operate

Diagnostic procedure
STEP INSPECTION ACTION
Yes Go to next step.
1
• Is ALC function operating?
No
Make ALC function operate, then go to Step
5.
Yes Go to applicable DTC inspection.
2
• Inspect DTC of PCM.
• Is DTC P0500 (VSS circuit malfunction)
displayed?
No Go to next step.
Yes Go to next step.
3*
• Disconnect audio unit connector (24-pin)
and ABS HU/CM connector (28-pin).
• Is there continuity between audio unit
connector (24-pin) terminal 1I and ABS
HU/CM connector (28-pin) terminal 1V?
No
Repair wiring harness between audio unit and
ABS HU/CM, then go to Step 5.
Yes
Repair wiring harness between audio unit and
ABS HU/CM, then go to next step.
4
• Inspect wiring harness between audio unit
connector (24-pin) terminal 1I and ABS
HU/CM connector (28-pin) terminal 1V for
short to ground.
• Is there short to ground?
No
Replace base unit, then go to next step. (See
AUDIO UNIT DISASSEMBLY/ASSEMBLY
.)
Yes
Complete troubleshooting, then explain
repairs to customer.
5
• Does ALC operate normally?
No
Recheck malfunction symptoms, then repeat
from Step 1 if malfunction recurs.
(w) RX-8 Body
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