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cst2099
08/22/2015, 07:44 PM
I know there are tons of threads about this but I just need some more help.

TOD check light is constantly flashing. (Code 13; grounded wire)
Rear wheels are lit and do not blink.
Front wheels never light up unless I engage 4L.
ABS light is always on. (Before I pulled the bulb) ;)

I have looked at all the wiring I can access and pulled the seat out to check the TOD unit itself and everything seems to be ok, no melted wires or harnesses.

Is there a common "problem area" that I check for grounded wiring? I'm pretty sure they're independent systems but could the ABS fault have anything to do with it?

Y33TREKker
08/23/2015, 09:07 AM
I know there are tons of threads about this but I just need some more help.

TOD check light is constantly flashing. (Code 13; grounded wire)
Rear wheels are lit and do not blink.
Front wheels never light up unless I engage 4L.
ABS light is always on. (Before I pulled the bulb) ;)

I have looked at all the wiring I can access and pulled the seat out to check the TOD unit itself and everything seems to be ok, no melted wires or harnesses.

Is there a common "problem area" that I check for grounded wiring? I'm pretty sure they're independent systems but could the ABS fault have anything to do with it?
From the 2000-2001 Electrical Troubleshooting Manual

"The T.O.D. control unit receives an input from the ABS system, when active, to apply voltage to the clutch solenoid (transfer).

Are your ABS related fuses good? CB-13, CB-16, EB-17?

(CB-4 must be good if your ABS light is on.)

Is the Code 13 a reference to a P0713 code (Transmission Fluid Temperature - TFT) Sensor Circuit High Input?

cst2099
08/23/2015, 10:41 AM
I confirmed that all fuses are good. I got the code from jumping the OBD connector and reading the flashes that show on the TOD display.

If the ABS module is shot, I'm wondering if getting it rebuilt may solve the problem.

Extra info: it's done this since I bought it over a year ago. Since then I've put a new transmission. The mechanic wasn't able to track down the problem either.

Y33TREKker
08/23/2015, 12:55 PM
Did you go through the steps to clear the TOD codes and see if the #13 came back?


1. Block wheels

2. Shift the transfer lever to the position between HIGH and 4L, and short circuit the self-diagnostic connector (Terminal 8 to ground). (Note, the neutral position between HIGH and 4L refers to the point that turns off the TOD indicator lamps. (However, be sure to check the position before short-circuiting the self-diagnostic connector).

3. Turn on the starter switch while maintaining the state of step 1, and step on the brake pedal five times within five seconds from the first step on. (Note that "five times" includes the first step on). (The TOD indicator lamps display the 4L mode whenever the brake pedal is stepped on.)

4. If the conditions shown in steps 1 and 2 are met, clear the trouble codes saved to the control unit. (After the codes are completely deleted, the code 12 indicates the normal condition).

The control unit itself rarely fails.


For a code 13, the manual suggests checking both the front and rear speed sensors on the rear of the transmission, but my first inclination would be to check the electrical connector H-27 (and it's neighbors) located inside the passenger side frame rail in the vicinity of the third cross member.

If you support the rear of the transmission and remove the transmission cross-member support, you'll find a wiring harness with a few electrical connectors in that general area.

Simply disconnecting those connectors, cleaning them with an electrical component cleaning spray, applying some dielectric grease, reconnecting, then applying some sort of waterproofing protection (shrink-tubing, electrical tape, etc) could do the trick. I had water get into those connectors once and my TOD control went crazy until it dried back out. (I subsequently completed the steps I just outlined and haven't experienced the problem again.)

cst2099
08/23/2015, 01:35 PM
Thanks so much for your help. I'll see if I can find a way to get at those connectors on the tranny. I've tried clearing the codes the way you described but it never worked. I even pulled a TOD ECU from a Trooper to see if that would help.

Y33TREKker
08/23/2015, 02:06 PM
Thanks so much for your help. I'll see if I can find a way to get at those connectors on the tranny. I've tried clearing the codes the way you described but it never worked. I even pulled a TOD ECU from a Trooper to see if that would help.
It wouldn't hurt to also check and waterproof the connectors coming out of the rear passenger side of the transmission, but just to verify, the connectors I've described aren't actually attached to the transmission. They're just part of the wiring harness in that area.

The fact that you tried a different ECU and still experienced the same code suggests the problem is in the harness itself, that is, assuming that the front and rear speed sensors from the original transmission weren't swapped over to the new transmission. It's still possible that one of the speed sensors or the malfunctioning ABS unit is the culprit.

Just hoping the help actually helps. :winko: