| Author |
 Topic  |
|
|
Palli
New Member
9 Posts |
 Posted - 05/08/2014 : 08:06:49 AM
|
Hey guys.
I'm having a problem with one of my buses. It's not shifting from first gear.
The ABS light is on in the dashboard and I'm getting the following flash codes when I press the engine diagnostic button:
111-No faults detected.
131-Accelerator position signal out of range LOW
141-Vehicle speed signal out of range LOW
626-Unexpected reset fault
When I connected it via a cable to my PF-Diagnose software I also got these:
RF Sensor Current below normal or open
RF Sensor Abnormal frequency pulsewidth or period
RF Sensor Abnormal rate of change
I changed the output speed sensor. But that didn't change anything.
Any thoughts or ideas on what I should be focusing on? |
|
|
earl1412
Senior Member
101 Posts |
Posted - 05/08/2014 : 12:28:37 PM
|
The ABS light is caused by the right Front wheel sensor being either bad or away from the tone ring too far. Try tapping the sensor LIGHTLY toward the ring. The trans not shifting may be the switch at the shift linkage on the trans. I've had a couple of these go bad, causing all kinds of goofy stuff.
As for the Accelerator, if you can, check the reference voltage using your scan equipment to see if it indeed had gone bad.
Maybe this will help.
earl |
 |
|
|
second.flood
Top Member
USA
640 Posts |
Posted - 05/08/2014 : 12:37:51 PM
|
Also the RF sensor wire may be rubbing the rim.
|
|
|
|
Farmridge
Senior Member
51 Posts |
Posted - 05/08/2014 : 1:03:30 PM
|
Check your wiring at the RF modulator to the wheel sensor, and modulator to the ABS controller. Check your wheel bearing play. Check your tone ring to see if it is bent or caked with grease and dirt. ensure your sensor is all the way in.
As for the engine codes, 131, 141 and 626 all sound as if you have a loose connection or ground somewhere. The 626 codes that I have ran into can be any where from the cables in the batter box with the fuses to the wiring harness under the hood. Check the connections by the left side of the engine underneath that have read and white wires. |
If you can't handle the answer, don't ask the question |
|
|
|
Palli
New Member
9 Posts |
Posted - 05/09/2014 : 02:34:51 AM
|
Thank you all very much.
I will get to it and post my progress.
Palli |
|
|
|
Winn10
Active Member
49 Posts |
Posted - 05/09/2014 : 3:48:28 PM
|
| Palli, the first thing I would repair is the abs light. with the abs light on, your torque converter will not achieve lock up, causing unnecessary transmission wear. more than likely your trans fluid is "dirty" restricting flow through the screen on shift solenoids causing it to shift/stick in the previous gear. let us know what you find |
|
|
|
Palli
New Member
9 Posts |
Posted - 05/10/2014 : 06:28:42 AM
|
First of all i want to thank you all for helping me out!
So i got started yesterday and found that the RF sensor cable was damaged. So i fixed that.
But then i visually inspected the rest of the cables and followed them to the Bendix ABS ECU I found a serious problem.
It's almost like it was attacked by an acid monster. It was literally falling apart from corrosion.
So needless to say there is some serious connection problems at the ECU. When i pressed on the cable and looked up the codes afterwards trough my PF diagnostic i only had one active code: SID:002/FMI-05 (RF Sensor Current below normal or open)
I did change the ATF and filter a few days ago. Thank you Winn10 for the info about the lock up. I just talked with the operators of the bus and they told me that the ABS light was on all last year. And the shift linkage was apparently replaced a few hundred miles ago because of problems getting the transmission in to gear.
So my plan now is to order the ABS ECU, inspect/measure wires from the 3 speed sensors on the transmission, replace the two remaining sensors (turbo and engine speed) and any other suggestions you guys might have.
I haven't started on the grounding problems that were suggested to cause the 3 Inacative codes i posted in my original post.
I have found a photo that i think is the same ECU http://mcicoach.com/service-support/technicalTrainingWebinar/abs042314/abs042314/files/assets/basic-html/page38.html
But i haven't found a site were to order it from. Any suggestions concerning that?
Or on a good site that can ship internationally?
I'm in Iceland by the way.
Also all sugestions/tips/tricks are greatly appreciated.
Thanks,
Palli |
|
|
|
Palli
New Member
9 Posts |
Posted - 05/23/2014 : 08:09:40 AM
|
Hey guys,
Does anyone have a wiring diagram of the 5 (actually there are 6 pins on the sensor #131040) wire harness that connects to the APS?
If anyone is following this then I have replaced all three speed sensors on the AT. I also took the ABS ECU apart and cleaned it. Then cleaned all connections that belong to the ABS system and fixed two wires that were damaged. Now I'm just waiting for the ABS sensor. Then I'll have no active/inactive codes on the brake module.
I have already ordered a new accelerator position sensor (APS) and I'm just waiting for it to arrive.
For what I understand the APS is basically the same sensor as the throttle positioning sensor TPS so that I hope is the reason for the transmission not operating as it should.
The only thing I'm not entirely sure on is the reason why the speedometer won't show any reading?
It does the regular check when I turn the ignition but does not move when I drive the bus.
Is the speedometer governed by the APS in any way?
|
|
|
|
Invader440
New Member
6 Posts |
Posted - 06/10/2014 : 5:21:20 PM
|
| Check the 2 plugs at the transmission shift module. We've had problems with two of our buses where the bigger plug has come out and it limits the tranny to first gear. We solved the problem by zip tying the plug so it can't come loose. |
|
|
|
Palli
New Member
9 Posts |
Posted - 06/20/2014 : 09:55:23 AM
|
Thank you all for your suggestions and help. I've gone through everything on the that has been suggested and no luck still :(
There is one thing worth mentioning, I think. That is after I replaced the throttle positioning sensor TPS I got the Instrument cluster up on the modules, on the PF diagnostic software. That had not happened before and has not happened again. ?
The only modules I do get up on the software are the Engine and the ABS module.
But can anyone tell me why the speedometer does not come in???
I thought it was controlled by either the TPS or the 3 speed sensors on the transmission! |
|
|
|
sambrutay
Advanced Member
United States
271 Posts |
Posted - 06/23/2014 : 04:44:31 AM
|
| So, all this talk about codes and allison problem of not shifting. yet I have not heard mention of any trans codes. is your check trans light on? power to trans ecu? |
Bruce |
|
|
|
Palli
New Member
9 Posts |
Posted - 06/25/2014 : 04:30:57 AM
|
Hi Bruce,
Yes the check trans light comes on as I start driving and the engine turns 1800-2000rpm
I don't have a drop box from Allison and the PF diagnostic software does not read codes from the transmission, so I don't have any codes from the transmission.
I've inspected all the wires that lead to and from the transmission, including the one's that are on the trans ecu. But I have not measured them.
Unfortunately I made the mistake of ordering a wrong ABS sensor from ebay the other day. So I'm still trying to find the right one, before I order again. Can you point me in the right direction, where to find the sensor for the bus?
Palli |
|
|
|
sambrutay
Advanced Member
United States
271 Posts |
|
|
Palli
New Member
9 Posts |
Posted - 07/28/2014 : 03:54:22 AM
|
Thank you all for assisting me in finding a solution for the problem.
I'm glad to inform that the problem no longer exists.
It was a combination of things.
First of all the socket for the data cable was not working correctly since there was a wire that connects to the transmission that was offline.
Then I also found out that to be able to communicate with the transmission trough the PF diagnostic software I had to switch to J1939 protocol.
Then I noticed that both the output speed sensor and the Turbine speed sensor where not level.
I also found out that on the TCM that the wire that goes to pin #15 on the RED/J2 socket was damaged.
On top of all the Instrument cluster was also full of dust and it may have been responsible for some of the issues.
I haven't changed the ABS sensor but the bus still started working.
So for all of you who have a problem like I just described I strongly recommend the link that Bruce posted and then focus on the speed sensors and the wiring around them.
Palli |
|
|
| |
Topic |
|
Navistar 3800 school bus allison 2000 problem
