# ABS codes **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [January 31, 2014, 11:27pm UTC](https://community.cartalk.com/t/abs-codes/83463 "2014-01-31T23:27:36Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![rotoway](https://avatars.discourse-cdn.com/v4/letter/r/a698b9/32.png) [@rotoway](https://community.cartalk.com/u/rotoway)\ **Post date:** [January 31, 2014, 11:27pm UTC](https://community.cartalk.com/t/abs-codes/83463/1 "2014-01-31T23:27:36Z")
What is ABS code 18 2001 PT Cruiser ---
**Author:** ![rotoway](https://avatars.discourse-cdn.com/v4/letter/r/a698b9/32.png) [@rotoway](https://community.cartalk.com/u/rotoway)\ **Post date:** [January 31, 2014, 11:32pm UTC](https://community.cartalk.com/t/abs-codes/83463/2 "2014-01-31T23:32:42Z")
Can anyone tell me what ABS code 18 means for a 2001 PT cruiser ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [February 1, 2014, 2:08am UTC](https://community.cartalk.com/t/abs-codes/83463/3 "2014-02-01T02:08:21Z")
Code 18= Brake Pressure Switch Circuit Malfunction. Tester ---
**Author:** ![rotoway](https://avatars.discourse-cdn.com/v4/letter/r/a698b9/32.png) [@rotoway](https://community.cartalk.com/u/rotoway)\ **Post date:** [February 1, 2014, 4:25am UTC](https://community.cartalk.com/t/abs-codes/83463/4 "2014-02-01T04:25:43Z")
Would the brake pressure switch problem be in the ECM or PCM ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [February 1, 2014, 4:38am UTC](https://community.cartalk.com/t/abs-codes/83463/5 "2014-02-01T04:38:06Z")
I don’t own a PT cruiser, but I would think the brake pressure switch is located on the master cylinder ---
**Author:** ![BustedKnuckles](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bustedknuckles/32/25_2.png) [@BustedKnuckles](https://community.cartalk.com/u/BustedKnuckles)\ **Post date:** [February 1, 2014, 4:52am UTC](https://community.cartalk.com/t/abs-codes/83463/6 "2014-02-01T04:52:29Z")
@rotoway, the code says ‘Brake Pressure Switch **Circuit** Malfunction’. This means the ABS module is not reading a proper signal from the switch. Most of the time, the fault is typically in the switch, but sometimes it is in the connectors or the wiring. Rarely is it the module. Testing the switch is generally done to confirm it is bad before replacing it. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [February 1, 2014, 5:01am UTC](https://community.cartalk.com/t/abs-codes/83463/7 "2014-02-01T05:01:42Z")
From what I can see there’s a brake fluid level switch on the master cylinder. Doesn’t have anything to do with brake pressure though. Just the level remaining in the bottle. Still, maybe that is what the code is referring to. Or maybe it is referring to the stop light switch, that at least has something to do with the brake pressure, although that switch I think is actually on the brake pedal. I guess the most important thing for now is to make sure the brake fluid level is up to the mark. And verify the brake tail lights are working. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [February 1, 2014, 5:06am UTC](https://community.cartalk.com/t/abs-codes/83463/8 "2014-02-01T05:06:59Z")
Yes, you are of course correct db4690. But the bottle (fluid reservoir) is _quite near_ the master cylinder I expect. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [February 1, 2014, 5:08am UTC](https://community.cartalk.com/t/abs-codes/83463/9 "2014-02-01T05:08:48Z")
I just deleted my post because rockauto doesn’t list a pressure switch OR a level switch So I’m not speculating any more on this car ---
**Author:** ![rotoway](https://avatars.discourse-cdn.com/v4/letter/r/a698b9/32.png) [@rotoway](https://community.cartalk.com/u/rotoway)\ **Post date:** [February 1, 2014, 5:48am UTC](https://community.cartalk.com/t/abs-codes/83463/10 "2014-02-01T05:48:21Z")
I’ve replaced theABS unit with a used one from a junk yard. That they claimed it only had 45k on it. The same problem still there. ABS and trac light. There is no pressure switch on the master cylinder. All fuses are good checked them twice ---
**Author:** ![BustedKnuckles](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bustedknuckles/32/25_2.png) [@BustedKnuckles](https://community.cartalk.com/u/BustedKnuckles)\ **Post date:** [February 1, 2014, 6:02am UTC](https://community.cartalk.com/t/abs-codes/83463/11 "2014-02-01T06:02:16Z")
You’re throwing money away. What made you think the problem was in the ABS module? The code is for a brake pressure sensor that could be in the brake line anywhere. If you insist on doing your own diagnostics, I suggest you pay a bit for a Factory Service Manual. The money you drop on it will pay for itself with diagnostic procedures, part locations, wiring diagrams, and proper repair procedures that will save you time and possibly breaking parts. There are a lot of factory manuals available at Ebay, but make sure you’re looking a FACTORY manuals, not Haynes, Chiltons, or other DIY manuals that are not as complete. I have a factory service manual for my Supra that has proven indispensable in keeping it in tip-top shape. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [February 1, 2014, 7:54am UTC](https://community.cartalk.com/t/abs-codes/83463/12 "2014-02-01T07:54:58Z")
@rotoway Do you have . . . or do you have access to . . . a scanner that does abs? ---
**Author:** ![rotoway](https://avatars.discourse-cdn.com/v4/letter/r/a698b9/32.png) [@rotoway](https://community.cartalk.com/u/rotoway)\ **Post date:** [February 1, 2014, 8:09am UTC](https://community.cartalk.com/t/abs-codes/83463/13 "2014-02-01T08:09:00Z")
I have a innova 3130c that brings up ABS code 18 . I’ve contacted innova and they said it was a Chrysler code and not in there system. I’ve contacted Chrysler they transferred me to a dealer. The dealer told me that ABS code 18 did not match any of there codes. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [February 1, 2014, 8:17am UTC](https://community.cartalk.com/t/abs-codes/83463/14 "2014-02-01T08:17:33Z")
@rotoway The guy in the story has a different Chrysler, but there’s some good information here > **[2005 Pacifica ABS Code 18 from Innova ODB2 . ABS Reader Seems to indicate...](https://www.justanswer.com/chrysler/81c8i-2005-pacifica-abs-code-18-innova-odb2-abs-reader-seems-indicate-brake-pressure.html)** > > 2005 Pacifica ABS Code 18 from Innova ODB2. ABS Reader Seems to indicate brake pressure switch problem? ABS light - Answered by a verified Chrysler Mechanic ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [February 3, 2014, 3:09am UTC](https://community.cartalk.com/t/abs-codes/83463/15 "2014-02-03T03:09:10Z")
OP should consider to have a Chrysler dealership diagnose this problem. Or at least a shop owning the Chrysler specific scan tool. The Chrysler scan tool is probably the only one that will provide an unambiguous result. ABS “Code 18” appears to be meaningless.