ABS/EPC/etc. warning lights

[bigfatgeek]

Hi all -

I've been having some dash warning lights come on periodically as of late. I'll be driving and then notice that the ABS or EPC and (/!\) (circle with a triangle and exclamation point) lights will come on. Sometimes the ABS or EPC light will then switch off after 10-20 minutes, but the (/!\) light will stay on until I restart the car.

Restarting it at any time will clear out the fault code. Oh, and the van has ≈66k miles on it (if that matters).

IIRC, this problem may be related to the ignition switch(?) I tried searching but came up with nothing, probably because I suck at searching with the forum software.

Any advice/insight is appreciated.

[trainwrecks]

it might be your brake booster?..found out about a week ago that i need to replace the brake booster then two days later the ABS/ESP came on.....

[bigfatgeek]

Did your EV give you any indication that the brake booster was going? Everything feels okay when driving my van.

[gti_matt]

Ignition switch or brake light switch is usually the culprit of these sorts of things.

[chendermi]

I agree about the brake switch. If you have access to a code reader, a faulty brake switch should show up. Then again, it's about a $20 part that is known to fail, so simple solution is to replace it anyway.

If it's not the brake switch, I'd next take a look at the infamous wire bundle between the front door and the body to look for breaks (pull back rubber boot and unwrap tape to check wires).

[bigfatgeek]

Cool, thanks for the tip on the switch, I'll order one up today (only $9 from Europarts-SD). Might as well replace the cheap stuff first...

[84GTi Guy]

break light switch most likely. Changed mine about 2 weeks ago. been fine since. Code was showing on vag-com. By the way i used a switch from a mkiv golf/jetta other than then the 1st set of #s in the part number which designate model, the rest of the # was the same and everything plugs right in. Check your local dealer, $5 and change for the switch @ my local dealer. bought a few last time i was there when my sisters golf brake switch went.

[bigfatgeek]

Thanks 84GTIguy, was it easy to replace? I'm a hack. I haven't poked around the van yet to see where it resides.

[luckeydoug1]

A faulty brake switch was the culprit on mine as well.

[chendermi]

Yeah, it's very easy to replace. I know europarts-sd includes instructions--probably others do, too.
Unclip electrical connector, twist switch and pull out. Installation is reverse.

[bigfatgeek]

Cool, I should have it today - I'll give 'er a whirl tonight. Thanks all!

**Super-easy to install, I spent more time walking into the house to get the key than I did under the dash.

[BlkMrktMondo]

My 2001 EV MV has the ABS light, the (/!\ ) light and the EPC light on; the EPC light comes on and off intermittantly and when it does, the van stalls when at a standstill and a noticable reduction in power occurs if being driven; then, after being driven for a few miles, it will turn off and a noticable increase in power happens.



Could this also be related to the brake switch? I would really love to take care of this issue myself and for little $.

Thanks in advance for any help

[bigfatgeek]

My van is noticeably better, I had a local VW shop clear out all of the codes the day after I swapped the brake switch - BUT...

the EPC light came on twice during freeway speed driving the day after the codes were cleared and the check engine light came on while driving it this afternoon. No ABS light though.

Thankfully I don't have to rely on my EV as a daily driver, I'll probably bring it back to the VW shop within the next week or two to have them check it out.

[BlkMrktMondo]

My van is noticeably better, I had a local VW shop clear out all of the codes the day after I swapped the brake switch - BUT...

the EPC light came on twice during freeway speed driving the day after the codes were cleared and the check engine light came on while driving it this afternoon. No ABS light though.

Thankfully I don't have to rely on my EV as a daily driver, I'll probably bring it back to the VW shop within the next week or two to have them check it out.

Mine has the same issue (I replaced my brake switch today) - please let me know what the dealer says...

[bigfatgeek]

@BlkMrktMondo - turns out it was the mass airflow sensor that was bad, triggering the check engine light. Just a coincidence that the brake switch was faulty at the same time. Or maybe not a coincidence, aren't these VWs known for electrical gremlins?

It'll be replaced tomorrow.

-Chris

(BTW - it's good to see a fellow bicycle industry member here...)

[BlkMrktMondo]

@BlkMrktMondo - turns out it was the mass airflow sensor that was bad, triggering the check engine light. Just a coincidence that the brake switch was faulty at the same time. Or maybe not a coincidence, aren't these VWs known for electrical gremlins?

It'll be replaced tomorrow.

-Chris

(BTW - it's good to see a fellow bicycle industry member here...)

I replaced my mass flow sensor yesterday (my local dealer had one) and I replaced it myself; Engine light is off; EPC light has yet to come back on (fingers crossed). ABS and (/!\) are still on; so the search continues...

[bigfatgeek]

Spend the $8 and buy a replacement brake switch. That should take care of your ABS and (/!\) lights. Good luck!

[chendermi]

Check fuse 14 in the main panel by your left knee. That's the fuse for the ABS controller. If blown, next thing to check is the wire bundle between driver door and body. Pull back rubber boot and start removing the black tape. Look for wire breaks.

A VAG-COM or equivalent code reader scan should also give you more clues. A generic OBD-II code reader will probably not help troubleshoot the ABS problems.

[BlkMrktMondo]

Spend the $8 and buy a replacement brake switch. That should take care of your ABS and (/!\) lights. Good luck!

I did that already to no avail...

Check fuse 14 in the main panel by your left knee. That's the fuse for the ABS controller. If blown, next thing to check is the wire bundle between driver door and body. Pull back rubber boot and start removing the black tape. Look for wire breaks.

A VAG-COM or equivalent code reader scan should also give you more clues. A generic OBD-II code reader will probably not help troubleshoot the ABS problems.

Hmmm....I'll do just that; thank you!

[MagicBus88]

What's the name of the part/product # did you order? I'm experiencing the same thing. Thanks

[bigfatgeek]

MagicBus - here's a link to the brake light switch I ordered:

http://store.europarts-sd.com/switch...2001-2003.aspx

If you need a mass airflow sensor, here's the link for that:

http://store.europarts-sd.com/airmas...2001-2003.aspx

Hope this helps.

[Jalendragon]

These same things all happened at the same time. The last week of november, the ABS light came on. Last night, I started getting all three lights, and while the EPC light was on, very low revving and idle.

EPC means the Mass airflow sensor's bad then, from what I have read in this thread?

(2003 GLS)

[bigfatgeek]

@Jalendragon - That was the case for me, since the mass airflow sensor was replaced a few years ago, the van has been trouble-free.

[Jalendragon]

Well, I had found that my intake hose had cracked, so I thought that was the problem. Having repaired it, I'm still having the problem, Rough idle, misfires, and the EPC code with the check engine light.


Could the MAF gone bad at the same time the air hose cracked?

[Jalendragon]

So I pulled the codes.

P0102
P0172
P0300
P0302
P0304

The first two are the only ones that really matter, the last three are all missfires due to the fuel/air mix. MAF circuit low input and Running rich Bank 1.

Now, here's the oddities. I decided to clear the codes and start it up to see what actually came across again. And... no codes. No hesitation, no misfires. Other than a very slight whine and a slight smell of epoxy when the air system came on, I don't have any issues.

My question now is, do I still replace the MAF just to be sure, or just clean it?