"N" light on 4x4 switch flickers

[jpimp]

Hello all,

2002 GMC Envoy SLT 4x4 with rear air. I noticed today that the red "N" light for neutral on the 4x4 switch is flickering. It flashes once every thirty seconds or so. Happened in Park and Drive, engine running. Everything else appears normal. IE: no lights on dash, and the 4x4 lights seems to do what they are supposed to do.

Any one know what this is caused by?

Thanks!

 

[AtlWrk]

With the ignition off cycle your switch back and forth all the way 100 times or so. Dirty contacts or a flakey switch maybe causing your TCCM to think you're erratically requesting neutral.

If the current mode light doesn't turn off at the same time the neutral flickers it is more likely a short on the brown wire between the transfer case switch and the TCCM. This is the neutral indicator light control--normally the TCCM grounds this wire to turn the light on. A short to ground might be causing it to flicker. This won't affect your 4wd operation.

 

[The_Roadie]

They redesigned the switch around 2005 to improve reliability. The new ones use the international symbols involving arrows for hi/lo. Old ones just lettering.

 

[jpimp]

Thanks for the great replies guys!

I exercised the switch before winter...been using it all winter...I will exercise it again tonight though.

Current mode light does not go out when the flicker occurs.

Didn't know that the arrow switches were newer...honestly just thought they were for the newer trucks...and my truck wouldn't like them.
Will try and get one.

Thanks Guys!

 

[The_Roadie]

Shockingly enough, they're cheap, even at the dealer. I think less than $30 list price.

 

[IllogicTC]

They redesigned the switch around 2005 to improve reliability. The new ones use the international symbols involving arrows for hi/lo. Old ones just lettering.

Must have been around the calendar year, not the model year. My Dec. 04-built 2005 model has the old style.

 

[jpimp]

Drove home from work and it was not happening...I'll try a switch and post back

 

[smt 59]

Mine had the old style as well but smoked the first year, replaced with new style under warranty.

 

[jpimp]

I don't think it has any thing to do with this problem...but sometimes when you start up the ride, the mode light on the 4x4 switch blinks until you move the vehicle or gear shift then goes on solid.
Correct me if I'm wrong but doesn't that just mean that a speed sensor is between cogs or something not to worry about it?

Then it happened while driving down the road too....(blinking selector light on 4x4 switch) but while driving the speed sensor shouldn't be between cogs...so now I'm wondering if this is a bigger problem...no codes.

Thanks Guys!

 

[The_Roadie]

I don't think it has any thing to do with this problem...but sometimes when you start up the ride, the mode light on the 4x4 switch blinks until you move the vehicle or gear shift then goes on solid.
Correct me if I'm wrong but doesn't that just mean that a speed sensor is between cogs or something not to worry about it?

Then it happened while driving down the road too....(blinking selector light on 4x4 switch) but while driving the speed sensor shouldn't be between cogs...so now I'm wondering if this is a bigger problem...no codes.

Thanks Guys!

What light specifically blinks? The one the switch is set to, or another one like 4LO or N?

There is no sensor issue about cogs. A non-moving speed sensor will just not put out any pulses and the TCCM sees that and knows you're not moving.

Failing a functional or communication test should light up the instrument panel light, not the mode switch.

Flashing mode switch lights means the TCCM has seen a commanded change and it's in the process of getting the encoder motor or front axle actuator to follow that command.

Still sounds like a flaky, flaky switch.

 

[jpimp]

What light specifically blinks? The one the switch is set to, or another one like 4LO or N?

The one the switch is set to. usually 2wd

Thanks for the replies!

Will get a switch and monitor