TOD CODES, 14 and 24

OK, so I just changed both front and rear TOD speed sensors with hopes to get rid of the codes 14 and 24.

CODE 14 = Front Speed Sensor - Input abnormality (open, sig or com)
CODE 24 = Rear Speed Sensor - Input abnormality (open, sig or com)

Obviously, my transfer case fluid was changed, and I was able to clear the TOD trouble codes by going through the steps in the manual, however the flashing comes right back as soon as I start up like normal, my TOD does not work, and I get codes 14 and 24.

Anyone else have this problem? In this thread:

http://vehicross.info/forums/showthread.php?t=21714

The OP states that the problem was the Transmission output sensor (OSS). He said he replaced this and it fixed it. But what is the Transmission Output Sensor? Obviously it is not the front or rear speed sensor, so what sensor is he talking about? Is it something in the transmission or another sensor in the xfer case?

Thanks- Bart

look carefully on wiring diagram. both sensors sit on only three wires off the TOD controller. trace wiring - might be wiring issue

Right, each sensor has 3 wires coming off it. All the wires I can see go up to the top of the tranny. I guess I need to pull the center console and inspect the wires under there on top of the tranny, if I can get to them.

Bart

I have a 2000 VX Electrical Troubleshooting Manual and it shows the Transmission Speed Sensor as being on top of the transmission to the left (drivers' side) of the transfer case shifter, and underneath the Auto-X shifter assembly. If you have one of these manuals, it's picture #62 in the back.

Quote:

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Originally Posted by nfpgasmask

Right, each sensor has 3 wires coming off it. All the wires I can see go up to the top of the tranny.
Bart

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on top of transfer case is big 12or16 pin connector then wire loom runs down to pass.side. tod controller is under passenger seat.

Thanks, I do have that manual, I will check it out. I got a PM from Scoobymlr and he verified this is the same sensor he replaced to fix this issue. Odd because the codes point to the front and rear speed sensors.

Now I just need to find this part. I'll be calling Merlin tomorrow.

Thanks - Bart

Quote:

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Originally Posted by nfpgasmask

Right, each sensor has 3 wires coming off it. All the wires I can see go up to the top of the tranny.
Bart

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on top of transfer case is big 12 pin connector then wire loom runs down to pass.side. tod controller is under passenger seat.

I was using trooper repair manual to fix issues with mine. on p590 is wiring diagram on p596-pin layout of that big 12 pin connector on top of transfer case and p610- diagnostic flow for codes24 and 14. in my case was rear speed sensor wire pin rotten.

Quote:

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Originally Posted by Dmitrikr

on top of transfer case is big 12 pin connector then wire loom runs down to pass.side. tod controller is under passenger seat.

I was using trooper repair manual to fix issues with mine. on p590 is wiring diagram on p596-pin layout of that big 12 pin connector on top of transfer case and p610- diagnostic flow for codes24 and 14. in my case was rear speed sensor wire pin rotten.

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I replaced both of these sensors yesterday, and they did not fix the codes my TOD is putting out. And according to 3 other people who have been down this road, those two (EXPENSIVE) sensors do not fix this problem.

It looks like it is illustrated here:

http://catalogs.marketparts.ru/isuzu...fHA1MD09MDI%3D

I think it is part # 8-96014-422-0, A/T CONT REVOLUTION SENSOR. I will be calling Merlin to check price on this tomorrow. Probably another pricey part but likely a non-Isuzu part can be used, since we are talking about the GM 4L30E here.

Bart

Here is a scan from the manual. I'm really hoping this is the problem.

http://www.isuzugeek.org/forumpics/vx/vxoss.jpg

Looks like it should not be too difficult to access.

Bart

try to disconnect it and drive with sensor disconnected and check for codes. I think if that sensor at fault will set ABS codes and possible MIL engine.

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Originally Posted by Dmitrikr

MIL engine.

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MIL engine???

Bart

Malfunction Indicator Light or Check Engine

Well, my ABS is completely gone, ripped that out a long time ago, but from my understanding the ABS and the TOD are completely different systems.

Bart

TOD uses some data of ABS module such as vehicle speed, brake pedal application etc. if I remember correctly

Quote:

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Originally Posted by Dmitrikr

TOD uses some data of ABS module such as vehicle speed, brake pedal application etc. if I remember correctly

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Well, according to Jerry Lemond, the TOD and the ABS systems are completely separate. Furthermore, my ABS has been dead and gone for years and I did not have this problem until recently.

Bart