ABS 4ws and error code help

bill · Post by **bill** » Sat Jul 27, 2013 1:30 pm

Im trying to diagnose what the problems are with my abs and 4ws. The abs light comes on and stays randomly usually coming on quicker the shorter the gap between trips. Ie if I was to switch the engine off in parking bay then switch it back on after 30 secs the light would come bqck on almost right away. The 4ws light only comes on aftet the ABS light comes on. At which point the 4ws system stops working. Until the light comes on the 4ws system works fine.

Error codes I think I get -
ABS code 4 & 8

4ws I get code 37 ? Its 3 long flashes then 7 short. It does this twice then rapidly flashes around 10 times which im assuming it is starting again?

Apologies if this has been covered as I hage read dozens of threads but cant find one with the same codes.

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sat Jul 27, 2013 1:37 pm

The manuals can be downloaded here which have all the info in them.

If the ABS system fails, the 4WS system will lock out after a while because it takes a feed from the ABS (speed) so focus on the ABS system first and you'll probably find there's nothing wrong with the 4WS.

ABS code 48 is rear left sensor.
4WS code 37 is Rear left wheel speed fault.

bill · Post by **bill** » Sat Jul 27, 2013 1:40 pm

wurlycorner wrote:The manuals can be downloaded here which have all the info in them.

If the ABS system fails, the 4WS system will lock out after a while because it takes a feed from the ABS (speed) so focus on the ABS system first and you'll probably find there's nothing wrong with the 4WS.

ABS code 48 is rear left sensor.
4WS code 37 is Rear left wheel speed fault.

So you believe it to be one fault on the ABS and not two seperate ? The reason i ask is because the flashes on the ABS seemed to be 4 short then 8short whereas the 4ws error was 3 long then 7 short?

Im hoping you are correct though as it looks like the two errors are conected

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sat Jul 27, 2013 1:51 pm

It will be the ABS sensor, yes. If you've got a multimeter though, just check it's the sensor rather than the wiring loom to it (it never is, but if you don't sods law it will be this time

). Unplug it (orange plug underneath the car) and check the resistance/continuity.
nb: when you go to replace it, be prepared for the bolts into the suspension arm to shear unlease you're really patient/gentle.

The 2 systems flash the codes slightly differently. The 4WS uses long/short combination for the 2digit code, the ABS uses short/short for the 2digit code.

bill · Post by **bill** » Sat Jul 27, 2013 2:00 pm

Awesome that sounds like its gonna be relitevly easy to fix (well for a garage anyway) Can I check the sensor without removing the wheel and without a working multimeter is it possible to figure it out either way?

The reason i ask is cos when i hand the car to the garage i want to give them a stack of parts for the different issues i have and hopefully ill get back a fully working prelude with no cheapo parts attached. Have you had to replace the sensor yourself and also where should i pick up the sensor?

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sat Jul 27, 2013 4:30 pm

Can't check the sensor without a multimeter really, no. There's no need to get the wheel off to test it, the plug is underneath the car on the inside end of the suspension arm, (so on the main body). You can find by lying under the car from the back and tracing the wire back off the suspension arm. Wheel needs to come off to replace it.

The only places I know of would be a Honda dealer (think they're around £120?) or second hand (probably around £30). As a general rule I prefer to use new parts than second hand too, but not when you can afford to replace it 4 times over by using a second hand one. I've used second hand sensors several times on ludes with no problems (different sensors each time!

)

For second hand, either breakers yards, ebay or on here (look in the cars breaking and parts sections or post up in the wanted section and see what response you get). The sensors are the same on any 4th gen that has ABS (engine, model year etc make no difference).

bill · Post by **bill** » Sat Jul 27, 2013 5:35 pm

Nice I had the wheel off today to get an idea of what needed replacing as I havent seen the sensor before. Seems the previous owner had the same idea and tried to remove the sensor and has threaded(sheared?) the bolt holding it in place, also explains the scratches on the skirt near the jack point from him taking the wheel off. Seems quite corroded under there tho so I think ill let a garage change it out for me. Do the sensors go often? I ask cos the last lude I had went 3 yr+ with the light coming on aswel , wasnt too bothered bout it tho as no 4ws .

When the 4ws light comes on do the wheels always lock inbplace or can they move freely? I ask cos going round bends at high speeds the back end seems to roll quite a bit.

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Sat Jul 27, 2013 6:52 pm

They're not that common to fail, but they do go. The car is 20 odd years old and the abs sensor cable is in a terrible environment - lots of water, salt, heat/cold extremes and an awful lot of flexing (more than anywhere else) so it's not surprising if the odd one goes.

In my experience I'd say prelude ones are more durable than abs sensors on other cars of similar age.

Unfortunately the bolts that secure them into the hubs and the cable to the arm do corrode badly though - they are a weak point, as it seems your cars previous owner has found. Might be worth you regularly spraying them up with wd40 between now and when you take it to the garage, to give them the best chance of getting them out.

When the 4ws goes into fault mode it sets the wheels central, but they aren't 100% secure in that position - think of it as though they're just held central with strong springs, so they're generally held in the correct position but that under strong cornering forces and bumps/ruts in the road, they can move. It's fine to drive normally (though you might feel the odd bit of movement) but avoid any hard cornering because it is much less predictable and the back might step out a bit.

Samiya85 · Post by **Samiya85** » Sat Jul 27, 2013 9:00 pm

I have a 2.2 4ws and abs working perfect
If u manage to figure out whts the problem i may able to help on the part

bill · Post by **bill** » Sun Jul 28, 2013 9:59 am

Yeah im defo gonna start with the abs sensor.

The sensors are the same on any 4th gen that has ABS (engine, model year etc make no difference).

Does this mean the front sensors would work also? I ask because on another thread I saw that the resistance is different from front to back? I found one on the bay hut its from the front. Ill post in the wanted section today if its no good