code 45

hey all, i have a '91 park avenue and the abs light has been on for awhile. i finally found a obd1 to read the code and it came up as a code 45 Lf inlet valve circuit.. any ideas what problem might be?? thanks

Check the info on that code in the PDF link. http://www.troublecodes.net/GM/93-95_34X.shtml

That means that the inlet pressure sensor inside the ABS pump is bad..

If you want to retain the ABS I would tell you to replace the ABS unit, or find one from a wrecker( You'd take your chances at a wrecker tho )...

I had an issue with a bad inlet sensor and ended up getting a known good ABS Pump and installed it right away.... Had a Bad Panic situation where a guy Puled out in front of me on a 50 MPH Highway through town... The car without ABS was a good bit harder to control, my only path was to head off road.. After that the ABS Pump went on that day... I don't care what anybody says, these C and H Bodies need ABS

Same code for my ABS. My doesn't work either it was on so long the light burned out before I even got the car. Seems to be a common problem. Wish I had ABS because on hard stops the back tends to lose traction on the left rear wheel and of course u can't steer. And when it rains I'm terrified of stopping. I really, really wish my ABS was working. Because I've had a couple of :yikes: encounters. But u can buy the unit for about $300 at advance auto parts.

thank you for the quick replies, i have a few park avenues to choose from at the u-pull it so im going to take my chances there first. now the pump is located under the air cleaner right?

Yeah its under the air box. Once you remove that u will have lots of space to work with. I think ABS will be a future project for me. I can't afford to do a hit and miss with a ABS unit from the junkyard. But I hope u find a good one.

This is the ABS Pump I yanked from my car.... Lots O fresh fluid went in... LOL
http://img.photobucket.com/albums/v294/Jr3800/95%20Bonneville%20Misc/DSC01830.jpg
http://img.photobucket.com/albums/v294/Jr3800/95%20Bonneville%20Misc/DSC01832.jpg

Is there a procedure to test to see if an ABS pump is good. I think I seen something on ALLDATA but I'm no sure. I'm having second thoughts.Maybe I can find a good one at the junkyard.:p I know one way to tell. My light bulb stayed on so long it burned the bulb contacts. Theres a nice brown spot around the bulb area on the lamp cluster. Maybe I should find one without the light cluster burned out.

Update: I was way off about the price of an ABS unit. It actually cost about $600.:eek7: The only way I would get one myself now is from the junkyard.

thanks for the pics jrs3800, yup, thats what i was looking at, hopefully this weekend ill go pick one up. ill keep you all posted. thanks again, sripvw

I apologize for the delay in posting. It may be academic at this point, but you can check the abs pump solenoids with an ohmmeter. Get a cheapie and take it to the junk yard and test the thing before you bring it home. In my case, the pickup cable in the wheel hub is torn up on the right front. But, I do have a spare pump from a junker just in case I ever get the initiative to replace that hub. IMO, that exposed cable is a major weak link of the system. Best of luck!

http://i98.photobucket.com/albums/l266/psue_1984/buick/abstest.jpg

Not to late, I probably pick one up and do it for a future project. So do you ground one end onto the ABS pump itself?

The diagram tries to show that you check continuity between pin 14 and the terminals referenced in the chart. So you would connect your meter between pin 14 and pin 3 and you should read 5 to 8 ohms. Pin 14 is common to all the solenoids/valves. There's another drawing in the repair manual that shows how the valves are wired internally. I can post that if you think it will help. The other connector is there to dive the motor/modulator/pump thingie.

I dug out the drawing showing what's going on internally to the ABS pump, see below:

http://i98.photobucket.com/albums/l266/psue_1984/buick/abs-diag.jpg

Cheers!