Alternator Fr Signal - Acura 3.5 RL Manual

Idle Control System
Alternator (ALT) FR Signal
This signals the PCM when the Alternator (ALT) is charging.
Inspection of ALT FR Signal.
Check for a short in the wire (ALT
F line):
1. Disconnect the GRN 4P con-
nector from the ALT.
2. Turn the ignition switch ON (II).
3. Measure voltage between PCM
connector terminals D5 and A26.
Is there about 5 V?
YES
Check the operation of the ALT:
1. Turn the ignition switch OFF.
2. Reconnect the ALT GRN 4P
connector to the ALT.
3. Start the engine. Hold the
engine at 3,000 rpm with no
load (in Park or neutral) until
the radiator fan comes on,
then let it idle.
4. Measure voltage between PCM
connector terminals D5 and A26.
Does the voltage decrease when
headlights and rear defogger are
turned on?
NO
Check for an open in the wire (ALT
F line):
1. Turn the ignition switch OFF.
2. Disconnect the negative bat-
tery cable from the battery.
3. Disconnect the PCM connec-
tor D (22P).
4. Disconnect the GRN 4P con-
nector from the ALT.
5. Connect the ALT 4P connector
terminal No. 4 to body ground
with a jumper wire.
6. Check for continuity between
body ground and PCM con-
nector terminal D5.
Is there continuity?
YES
See the ALT inspection
(see section 4).
Check for a short in the wire (ALT
F line):
1. Turn the ignition switch OFF.
2. Disconnect the negative bat-
NO
tery cable from the battery.
3. Disconnect the PCM connector
D (22P).
4. Check for continuity between
body ground and PCM con-
nector terminal D5.
Is there continuity?
NO
Substitute a known-good PCM
and recheck (see page
immobilizer information). If pre-
scribed voltage is now available,
replace the original PCM.
YES
ALT FR signal is OK.
NO
Repair open wire between the
PCM (D5) and the ALT.
PCM CONNECTORS
Wire side of female terminals
YES
Repair short in the wire between
the PCM (D5) and the ALT.
11-41 for
ALT GRN 4P CONNECTOR (C131)
Wire side of female terminals
PCM CONNECTOR D (22P)
Wire side of female terminals