98 Grand Voyager V6 3.0 Bought new rad fans & pwm 'relay'. No go...

For some background, see my posts here:
formatting link
!=topic/rec.autos.makers.chrysler/d-nN1f4nVAoAnyway I put in a new fan and a new relay, drove to work to warm it up good= and...nothing. What next? Anybody know how to check the connector to the r=elay with a digital VOM (with the car warmed up, checking for voltages)? I =haven't checked the fuse because the code #P1491 said fan relay. maybe I sh=ould check it in the morning. Doubt if that's it. This is driving me nuts A=ND broke. What do I do next?
Reply to
Mark Goodall
For some background, see my posts here:
formatting link
!topic/rec.autos.makers.chrysler/d-nN1f4nVAoAnyway I put in a new fan and a new relay, drove to work to warm it up good and...nothing. What next? Anybody know how to check the connector to the relay with a digital VOM (with the car warmed up, checking for voltages)? I haven't checked the fuse because the code #P1491 said fan relay. maybe I should check it in the morning. Doubt if that's it. This is driving me nuts AND broke. What do I do next? Grey/gray is B+ and is always hot even with the key off. Black is ground. Light green is fan output Dark green is PWM in
Since the PWM signal is a switched ground I would get a cheap analog multimeter and hook it to grey and dark green (once you are sure grey has good power) then turn on the A/C or get the engine hot, its voltage reading will show you the approximate PWM duty cycle, IE if the battery voltage is 14 and the meter reads 7 that is 50%. Digital meters don't do very well here unless they have a duty cycle/dwell readout that can handle whatever frequency the PCM puts out. If this test passes then jump grey to light green and see if the fans run.
Reply to
Daniel who wants to know
Daniel, the orange 40 amp fuse is fine. I'd run the test in the morning, but all I've got is a digital VOM. I'll try to hustle an analog from neighbors tomorrow. I'm I even asking the right questions anymore? Mark
Reply to
Mark Goodall

P1491 is Radiator Fan Control Relay *CIRCUIT*
The first step in the troubleshooting procedure is to check the Fused B(+) circuit for an open (which woulod incloude a burned out fuse).
Reply to
SRN
Yeah, SRN, I'm aware that it's a "circuit". Like I said, I checked the 40 amp fuse, and a week ago, I got +12v at pin 1 on the relay connector. Mark
Reply to
Mark Goodall

For some background, see my posts here:
formatting link
!topic/rec.autos.makers.chrysler/d-nN1f4nVAoAnyway I put in a new fan and a new relay, drove to work to warm it up good and...nothing. What next? Anybody know how to check the connector to the relay with a digital VOM (with the car warmed up, checking for voltages)? I haven't checked the fuse because the code #P1491 said fan relay. maybe I should check it in the morning. Doubt if that's it. This is driving me nuts AND broke. What do I do next? {{
I'll give it some though but in the short you can wire the fan so it blows when the ignition is on. I'd not do this in the dead of winter (then again maybe I would is it ment getting home) but in Summer I have and run it that way until the part came in.
Reply to
NotMe
Thanks, guys. I'm not going to bypass straight to the fans/ battery/ fusebo= x, because here in NW Indiana we have to=20 pass emission tests to renew plates and registration. Check engine light'= s an automatic failure. I haven't done the test still gotta find an analog VOM. I've got +12v to th= e relay connector and good ground, so when I run the test if it fails, what= do I do next? What am I missing? Temp sensor? My dash temp gauge works fi= ne. Is it possible (God forbid) that it's the expensive computer gizmo that= runs everything? I need to figure this out pretty quick. Any help is welc= ome. Mark Goodall
Reply to
Mark Goodall
My wife's picking up an analog VOM for $20 at the Shack, but she won't be back til 2 am. Meanwhile I'm going to go over everything and see if I missed anything. (for instance, even though the fan's new, I haven't checked it with the battery.) Thanks to Steve N. for the troublshooting guide. Can anybody tell me where the PCM module is physically located) Thanks, everybody. Mark Goodall
Reply to
Mark Goodall

For the PCM location check the inner left fender well next to the Power distribution center box.(which is next to the battery.
Reply to
SRN

This scan is out of the 2000 diagnostics manual. Location should be the same as the 1998 model
formatting link

Reply to
SRN
I'm having a hard time telling the difference between the 2 green wires on the relay connector. Rather than being dark & light green, mine are green & blue-green. Can anybody tell me whether the dark green is next to the black wire or next to the gray wire? They're also numbered 1 - 4 on the connector, so is dark green #2, or is it #3? I don't want to guess, so I can do the test right. Thanks, Mark.
Reply to
Mark Goodall
You said the pin #1 is melted. From the diagram, #1 is ground. It grounds the powertrain control system. So the diagram says that your power train control module is shorted. I think you need to find a new power module. get one from car-part.com..
you can get electronics from junkyards if you can be sure they are not expose to rain or snow.
com...
Reply to
u c coskun
Thanks, u c, that's what I was afraid of. Can you tell me where the power module is located on the minivan? Also, what other symptoms might the vehicle have with the power module shorted? Thanks, Mark.
Reply to
Mark Goodall

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.