Code 1641???

[redws6]

i had the ses light come on yesterday and i ran the odb2 tester and it came up codes 1641 and 1642??? they dont even go that high in the book the tester came with.....

the car runs perfectly fine. any ideas?

[dochidalgo]

These particular DTC's are referring to the Relays 1, 2 and 3, from the fan relay coils...our cars have 2 fans as you already know.....you'll need to replace them and check the terminals.
Good luck
Dochidalgo

[redws6]

does anyone know where these relays are?

[Rob B (shoebox)]

They are in the underhood fuse/relay panel.

Do you have a manual fan switch? It can cause the codes if not wired with some resistors to keep the PCM happy.

Click the DTC link in my sig for a listing of codes.

[redws6]

so does that mean the relays are bad? no i dont have a manual fan switch.

[Rob B (shoebox)]

It means anything between the PCM and the relays (incl relays and wiring) could be a suspect. You can swap the relays, one at a time, with the fog lamp relay and see if they work there. That will tell you if the relays are good.

[redws6]

do you have a pic of the fan relays or any idea which one is which. thanks for the help i appreciate it.

[Rob B (shoebox)]

Inside the panel cover is a diagram sticker showing what is what.

[redws6]

funny you should say that, for whatever reason, i dont have a cover on mine.....hmmm. nothing ever goes right. anyway im lookin around your site and i find it to be really informative, good job on the site.

[Rob B (shoebox)]

You really should get a cover. Water can get in the panel. That may even be your problem. Make sure you check fuses in there, too. Look in your owner's manual for the diagram. If you don't have an owner's manual go here.

[redws6]

thanks for the help man.

[redws6]

ok i bought relays but they said there for the flashers. would this make a difference. i plugged themin and it didnt work, so im guessin i had to get relays specifically for the fans?

[Rob B (shoebox)]

ok i bought relays but they said there for the flashers. would this make a difference. i plugged themin and it didnt work, so im guessin i had to get relays specifically for the fans?

Flashers? There are no flashers in the underhood panel.

Did you not test the relays as I suggested before buying new ones? The relays are pretty generic and used for a lot of things.

[redws6]

so i took back the relays, my friend stopped over and he tested to see if the relays were gettin any signal to them and there wasnt. so he thinks that maybe the temp sensor would be bad, but wouldnt that make my gauge not work too?

o and other than that, i have a bad ground connection in one of the lightbulb sockets in my rear tailight.

[Injuneer]

so i took back the relays, my friend stopped over and he tested to see if the relays were gettin any signal to them and there wasnt. so he thinks that maybe the temp sensor would be bad, but wouldnt that make my gauge not work too?

o and other than that, i have a bad ground connection in one of the lightbulb sockets in my rear tailight.

No. The gauge runs off a sensor on the drivers side head. The PCM/fans run off a temp sensor on the water pump housing. You can check the temp sensor with an ohm meter. There is a table of temp vs. resistance in my online scanner writeup, if you need it.

The fan relays wouldn't have gotten a power signal to turn them on unless the coolant temp was above 226degF.