Please help me! Can the t.case switch going bad cause the Jeep to throw out a code?

[ahjjones]

Hey,
So I've never really any problems with my Jeep, except the part-time light staying on when it's in 2wd. I'm having that fixed next Sunday, but lately the check engine light has been coming on, then clearing itself every three or four days or so. When my friend ran the code it was a code that he couldn't get on his scanner. He looked it up at work, and said the engine light was caused by the part-time light/transfer case switch going bad. Does this sound right? Can the t.case switch going bad cause the computer to throw codes? It seems to clear it self out, then the light comes on light three days after it resets. What gives?!
PS: I have my inspection due in March, so I'm freaking out. HELP!

 

[diyman]

According to the manual, these conditions do cause a P0836 DTC:

-TRANSFER CASE POSITION SENSOR PLAUSIBILITY
-TRANSFER CASE POSITION SENSOR SIGNAL VOLTAGE TOO HIGH
-TRANSFER CASE POSITION SIGNAL VOLTAGE TOO LOW

Unless it's a wiring issue, changing the sensor should solve it ( sort of PITA though... ).

No clue about inspection, just make sure to drive the vehicle a while after clearing the code.

Good luck

 

[ahjjones]

According to the manual, these conditions do cause a P0836 DTC:

-TRANSFER CASE POSITION SENSOR PLAUSIBILITY
-TRANSFER CASE POSITION SENSOR SIGNAL VOLTAGE TOO HIGH
-TRANSFER CASE POSITION SIGNAL VOLTAGE TOO LOW

Unless it's a wiring issue, changing the sensor should solve it ( sort of PITA though... ).

No clue about inspection, just make sure to drive the vehicle a while after clearing the code.

Good luck

Okay! So it could cause the engine light to come on? I was a bit confused by your answer, haha. Thank you!

 

[diyman]

Yes, I see the point.... Usually, transmission issues (P07xx) do illuminate the MIL. I guess this DTC is also considered transmission related...

Anyway, if the scan tool reports no other code, then You'd be OK, clearly... Again, check Emissions Readiness Status!

BDW, automatic or stick?

 

[tjkj2002]

What year is your Jeep?

A '02-'07 KJ that sensor just turns on a light in the dash(or off) and that is it and can not trigger a check engine light.In a '08+ KK it can turn on the check engine light since the t-case is electronically shifted.

 

[ahjjones]

Yes, I see the point.... Usually, transmission issues (P07xx) do illuminate the MIL. I guess this DTC is also considered transmission related...

Anyway, if the scan tool reports no other code, then You'd be OK, clearly... Again, check Emissions Readiness Status!

BDW, automatic or stick?

Automatic.

 

[ahjjones]

What year is your Jeep?

A '02-'07 KJ that sensor just turns on a light in the dash(or off) and that is it and can not trigger a check engine light.In a '08+ KK it can turn on the check engine light since the t-case is electronically shifted.

It's a 2003.

These are the codes I got:
P1491
P0838
P0837
Aren't the last two related to the transfer case switch?


Thanks in advance!

 

[diyman]

It's a 2003.

These are the codes I got:
P1491
P0838
P0837
Aren't the last two related to the transfer case switch?


Thanks in advance!

Sure, and almost certainly it's the P1491 that's turning MIL on (Radiator Fan Relay Circuit). Have wiring checked too.

Who knows, maybe just a bad relay and/or some contact cleaner, also on T/C sensor's connector :shrug: ...

 

[tjkj2002]

It's a 2003.

These are the codes I got:
P1491
P0838
P0837
Aren't the last two related to the transfer case switch?


Thanks in advance!

The last 2 codes do not apply to yoru KJ.I ran around for 2 months without that sensor even hooked up,no check engine light just the 4wd low light on in the cluster.Those last 2 codes are mainly labeled for clutch switches in manual trans vehicles.

 

[ahjjones]

The last 2 codes do not apply to yoru KJ.I ran around for 2 months without that sensor even hooked up,no check engine light just the 4wd low light on in the cluster.Those last 2 codes are mainly labeled for clutch switches in manual trans vehicles.

Hmmmm. So if "these don't apply to my libby" then why are these the ones I'm getting? Now I'm even MORE confused! When I had the scanner hooked up I got these, and I get them if I grab the codes myself, with the key technique.

Also, they don't have anything to do with the manual transmission. "P0837 -Four Wheel Drive (4WD) Switch Circuit Range/Performance, P0838 -Four Wheel Drive (4WD) Switch Circuit Low". What gives? :favorites68: How do I get rid of the engine light now?!