TTAC Commentator Kericf asks:
I have a 1998 Isuzu Rodeo 4×4 with the ABS light starting to come on intermittently. The first time it happened I thought I heard a clicking noise under the dash like a bad solenoid. I had to replace the solenoid for my turn signals once and it made a similar noise when they would go haywire. A lot of forums on the Rodeos point to bad speed sensor on the rear axle, but if it’s just a bad solenoid that would be easier. The truck has 214,786 miles as of this email and I am wondering if I should also worry about rubber brake lines deteriorating. I can’t find any leaks but I don’t want to blow a brake line in Houston traffic.
Sajeev answers:
First and foremost, check your rubber brake lines for cracking or collapsing. Even if you pay a mechanic for their trained eyes, that’s still cheap insurance. Then again, our Houston freeways have more than adequate shoulder room for an emergency run off.
More often than not, an illuminated ABS light is from a computer generated trouble code. You must, must, MUST check for this code before replacing anything on the system.
If you’re lucky, you can borrow the correct scan tool from a parts store ($100-ish deposit on your credit card) and pull the code yourself, for free. If not, expect to pay the standard diagnostic fee at a local shop.
Get the code and Google it for a diagnosis. I’m not a gambling man, but I’d bet on the speed sensor too: that’s a very common wear item on ABS systems. If accessible, clean the sensor and ring with a can of brake cleaner to remove any debris on its magnetic parts. That probably isn’t your problem, but it never hurts to first try a free fix.
As far as the clicking noise under the dash, it’s probably not ABS related [NB: I have never touched an Isuzu’s braking system] because most of the system is normally self-contained under the hood, including the wiring and modules.
[Send your technical queries to mehta@ttac.com]
Hmmm. A car from the 90s with over 200K miles. A small piece of black electrical tape carefully applied over the dash light solved the problem in my 96 Odyssey. This is probably not the answer you are looking for. Presuming that this is not about brake operation, but only about ABS operation, you should consider this solution if your problem turns out to be an expensive one. Maybe its my age (50) but I have driven hundreds of thousands of miles in non-abs cars and live to tell the tale.
I had this happen to my old ’93 Blazer at about 150k. ABS Control Module had to be replaced. New part was quoted at $1200+. Thankfully, I found a mechanic who was willing to pull one from a junkyard and put it in for $500 or so.
I had a 98 Rodeo. Man I miss that car. Traded it in a few years ago at 117k miles when we got our Odyssey, got ripped off on trade in by the Honda dealer, I know better now. In hindsight, I should have kept it, especially considering how little I got in trade in. It would have been the perfect 3rd car- drop the insurance coverage to liabiltiy only, use it on snowy days (both b/c of 4wd and b/c not worrying about muddy wet feet), to haul junk to the dump etc. The funny thing is, I really didn’t like the car all that much when I had it, but now I miss it.
I’m a bit of a contrarian on the ABS issue here. On many mid 1990s European cars, reading out the ABS code and fixing what it suggests actually leads you to do the wrong thing. ATE shipped hundreds of thousands, perhaps millions, of ABS controllers which were prone to failures of the internal traces which are connected to the sensors. Many a Volvo owner paid big bucks to get wheel sensors replaced because that is what the failure codes said to do, only to have the ABS light keep coming on. The only real solution was to replace the failed ATE module. I’m still ticked off at Volvo for never fessing up and issuing a recall on those things. The same modules were used in many other Euro cars as well.
Lucky for me, I followed brickboard.com and knew about the real scoop. Thus when the symptoms of intermittent ABS light coming on started on my ’96 850 I followed the wisdom of the net, not the flow chart of a scan tool. That saved me a great deal of expense and grief. Perhaps it is a similar situation with the Isuzu.
Another ABS fault I fixed was on my friends ’89 F150 with rear only ABS. The dealer wanted $100 to hook up a scan tool. I started with the basics and discovered that the fuse for the ABS system had failed. One new fuse and the ABS has continued to work like a charm for three years now.
Generally I agree with Sajeev that throwing parts at a problem instead of pulling the codes is a dumb move. But, I would replace that rear ABS sensors as a first move in this case. Since they are known to have a high failure rate, it doesn’t hurt to change it out even if that doesn’t fix the problem. You can consider it preventative maintenance. Same with the brake hoses. If they are original I would replace them all at this point. 11 years and over 200k miles is more than enough.
” … got ripped off on trade in by the Honda dealer … ”
Used Isuzus are worth almost nothing thanks to Isuzu’s retreat from the US light vehicle market. Maybe you should have kept it, but the dealer probably didn’t rip you off.
I have been really lucky with the truck. So far no major issues. Brakes lasted 180,000 miles before I had to change them. I bled the brakes when I changed them and didn’t notice any cracking on the lines or leaks then when I looked over eveything. I am just worried as someone above said, 11 years of use is a long time for a rubber hose. Another thing to think about, I found a set of replacement brake lines that are braided steel instead of rubber. Is it worth the money to get that kind of kit instead of rubber hoses.
We got 11 inches of rain about a month and a half ago and I ended up driving through so decently high water on the way to work and I’m thinking it might have screwed up the sensor. I’m going to stop at Advanced Auto on the way home to pull the codes.
The 98 Honda “Pissports” had a recall for the ABS control unit mounted to the side of the modulator. I’d guess the Isuzus had the same recall. Hope you can find a local Isuzu dealer to do it for you if not already done.
More likely if you pull the code it’ll be for that failed rear wheel speed sensor. Easy to replace in the rear diff housing.
Check the ABS harness before the rear axle
there is a connector or a splice that gets corrosion hope it helps.
poltergeist :
Ya, I already had this done a few years ago luckily. I have to go to a local Chevy dealer that used to sell Isuzus for parts I can’t get at an auto parts store so I’m pretty sure I would be SOL on any recall work that was pending witht he GM bankruptcy now.
I have 20yr old + brake hoses in my fleet. So, I wouldnt sweat 11 yr hoses unless there are visible issues. ABS sensors can be checked with a multi-meter. All 4 should have the same reading in, IIRC, DC milli-volts. As mentioned, clean off the debris from the wheels and magnets. May be apples and oranges , but when there is low system voltage on my 528e, the ABS light will come on. Failing this, electrical tape is your friend.
fleetwrench : Check the ABS harness before the rear axle there is a connector or a splice that gets corrosion hope it helps.
Another great idea that costs $0.00. A definite must-do in this case.
My 1995 Rodeo has had the same problem for the decade that I have owned it. The ABS light blinks when ever I hit a bump on the road.
I guess I could have spend thousands a replacement sensor, but why really?
The brakes seem to work fine despite the intermittent light.
Check all the ABS wiring you can get at. My mother’s car had an intermittent ABS light which eventually became constant. I found a broken wire right at the speed sensor. Easy fix.