Posted March 25, 201510 yr Hey gang been a while .... so busy lately.... Started today .... I've had ABS light for a while .... finally got around to changing both wheel hubs out a few weeks back .... no difference. Rear sensor seems clean. today speedo stopped ...... How to track down ;)
March 25, 201510 yr Owner If the speedometer quit then your rear sensor quit. Rear sensor seems clean. Appearance is meaningless. What matters that the sensor can produce a proper AC sine wave that ABS computer can use also that the 3 sensors all have the same frequency. If on is different that means that one is tripping the light and needs replacing. ABS system requires all sensors to match in frequency.
March 25, 201510 yr I believe that the DRB tool at the dealer can look at the individual sensors. This is recalled from other posts, as I haven't tried diagnosing this problem myself as of yet.
March 26, 201510 yr Owner Like down at work we've got a Innova handheld code reader that can read ABS errors and tell you which sensor is screwed up. Like this is a bit newer version than ours... http://www.innova.com/en-US/Product/Detail/3120d
March 26, 201510 yr Author So I had it on a high dollar scanner - not a DRB but a full suite scanner. No codes for ABS - only boost to high, injection pump (ppump) and TPS and grid heater. Q) - The front two sensors on the wheels only control ABS right ? So even if there was a damaged circuit - that wouldnt impact speedo and odometer. So basically the only fault for speedo/odometer could be the transmission sensor (auto) or the rear sensor ?
March 26, 201510 yr Ohm out the rear wires from under the hood. On my truck the junction above the drivers front was really beatup due to salt etc. I had to redo pretty much all wires in the loom.
March 29, 201510 yr Author Wires and sensor both ohm ok from the rear .... literally get a reading by closing circuit on sensor ... or on sensor harness Sensor looked fine ... no shavings ... teeth looked ok from what I could see New sensor on order here in a couple days Anything else to check ?
March 29, 201510 yr Author Ha ha .... where's the butt kick icon .... drive over and fixit for me then. Starting to wonder if ABS module is dead. Cluster is fine.
March 29, 201510 yr Seems like I remember people having abs light after p-pump swap, maybe just now catching up with you. Pull the bulb and keep on truckin!
March 30, 201510 yr Author Haven't heard that one. Not worried so much about ABS .... but speedo and odo
March 30, 201510 yr Rear diff sensor got my speedo back. Oem only, oriellys one failed. abs light is most likely the control module. Have a mechanic check it with the snap on reader and if it cycles on and off then it's bad
March 30, 201510 yr Owner Typically if the ABS light is on then there is a problem within the ABS system be it sensors or ABS controller.
March 30, 201510 yr Author So theres no interaction between sensors at front and speedo/odo ? Basically sensors at front for ABS only. Sensor at rear diff for speedo/abs ?
March 30, 201510 yr Owner So theres no interaction between sensors at front and speedo/odo ? Basically sensors at front for ABS only. Sensor at rear diff for speedo/abs ? Correct. The front two sensor have zero bearing on the speedometer only the rear sensor takes care of the speedometer and odometer.
March 30, 201510 yr Mine have ABS light comes on and off. Speedo is good. Had it check by mechanik drb tool and rear sensor area trouble. We found twisted wire connection with tape and some corrotion. I repair the wire that looks like burn and changed othing the sensor but nothing changed!! Maybe bad wiring all the way . Maybe your trouble???
March 31, 201510 yr Staff On some of the Volvos that I work on the Speedo get it's signal from the ABS control module. When the speedo goes out and the ABS light is on I open the module and solder the main power wire coming into the circuit board. You find that the solder joint is bad from the hot/cold cycling.
Hey gang been a while .... so busy lately....
Started today .... I've had ABS light for a while .... finally got around to changing both wheel hubs out a few weeks back .... no difference. Rear sensor seems clean.
today speedo stopped ......
How to track down ;)