code 1491, rad fan relay, please help
Hi, my 2002 dodge grand caravan sport 3.3 v6 is showing check engine light.
Code from key dance is 1491 which indicates rad fan relay circuit
problem, FANS DO NOT RUN. According to manual it could be relay,
wiring or PCM.
I am attaching an image with all wires going to relay circuit and with
all the voltage on them. fans do run but draw 16 amp when I jump
the circuit to them.
I changed the relay and disconnected the battery at same time.
when i started the van again, code 1491 disappeared . when i turned
switch off in 5 seconds and restarted van, code 1491 came back again.
there are four wires as in image,
Orange wire has 12 volts, Fuse is ok, when in Disconnect fuse, no voltage
on red wire. when i short this wire to light blue wire, fans run, resistance
between orange wire and battery positive terminal is less than 1 ohm.
light Blue wire goes to fans,
Black -green wire goes to lower connector of PCM, has ground all the
time, with resistance between this wire and PCM connector is less than
5 ohm. FAN do not run when i short this wire to ground.
Blue violet wire, has 12 volt all the time, even when switch is off, fan
run when i short this wire to ground, i could trace it to IPM where
resistance is less than 5 ohms. IF SWITCH IS OFF, AND I SHORT THIS
WIRE TO GROUND, FAN STILL RUN.
I WAS EXPECTING PCM WIRE, BLACK GREEN TO HAVE 12 VOLT ALL THE
TIME, AND GROUND WITH AC RUNNING,
AM I TRACING BLUE VIOLET WIRE WRONG, ANY CIRCUIT DIAGRAM MIGHT
Last edited by vitual; 03-10-2011 at 04:40 PM.
Reason: removing picture