4x4 dash lights
FishFind
07-01-2011, 12:04 AM
Hello I have a 1998 4x4 chevy blazer
w-vin
4.3L
I have a CODE: P0740 that is a TCC code,
I am not sure if it is related to the issue I am having but I am getting it professionaly scanned next week to find what is wrong.
Here is my problem. The only light that will blink and stay on is the 4x4low. I can hear it engage under the car for every selection, 4x4low 4x4hi and 2x2 hi but I only see it blink and go solid on the 4x4 low. The bulbs work because I can see them engage every now and then at random. Like I am in 2x2 hi and all of a suddon it will light up.
Any ideas? no vac leak and I hear it click in the glove box and under the car. It seems to work also because the 4x4 hi will make the rpm go up a little when pressed.
w-vin
4.3L
I have a CODE: P0740 that is a TCC code,
I am not sure if it is related to the issue I am having but I am getting it professionaly scanned next week to find what is wrong.
Here is my problem. The only light that will blink and stay on is the 4x4low. I can hear it engage under the car for every selection, 4x4low 4x4hi and 2x2 hi but I only see it blink and go solid on the 4x4 low. The bulbs work because I can see them engage every now and then at random. Like I am in 2x2 hi and all of a suddon it will light up.
Any ideas? no vac leak and I hear it click in the glove box and under the car. It seems to work also because the 4x4 hi will make the rpm go up a little when pressed.
Tony Silva
07-01-2011, 12:49 AM
Get ready for a hefty repair bill!!! 2002 Tahoe...same code....replaced trans module...replaced trans shift position indicator...replaced trans valve body. The only reason why the 4X4 light stays on is beacuse that is the only thing the computer is seeing as acting right...the computer gets the info from all the trans & transfercase sensors. My fix for this went on the VISA...$2,300 for a rebuilt installed transmission.
As a side note, I paid almost $1,200 for previous parts and diagnostics that did NOT fix the prob!!!
As a side note, I paid almost $1,200 for previous parts and diagnostics that did NOT fix the prob!!!
old_master
07-01-2011, 10:50 PM
P0740 is a problem with the transmission Torque Converter Clutch, (TCC) solenoid circuit. The ECM has detected an open circuit or a short circuit in the wiring to the solenoid, or the solenoid itself. The transmission oil pan may need to be removed to properly diagnose the problem. There is an electrical connector on the passenger side of the transmission, near the front corner of the transmission oil pan. There are several wires in the connector that run to the solenoids inside the transmission. Due to its location, it is subjected to water, dirt, and anything else that gets splashed on to it, plus vibration. An easy thing to check is make sure the connections are clean and tight. If that's not the problem, it will require electrical diagnostics to locate the cause.
FishFind
07-01-2011, 11:57 PM
I have dropped the pan once and did a OHM test. That came back fine. I did not know I can check it with a battery at the time and put it back on. Code is still there but I would never know of any problem if the light was not on; I dont know where the wires go to from the external wire harness to check them. I can check the internal ones or just get a new harness that has the TCC lockuo on it for $60. You know where the wires go from the external wire harness?
FishFind
07-02-2011, 10:53 PM
Dash lights fixed. Bad switch. noticed it would flick on over bump so pulled out and squeezed it. Started working.
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