ClackClack

FYI: WIF light comes on with my cluster test...

wreedCTD

well i just found out for myself.

if you hold the odometer reset button then turn the key to the run position it will run a cluster diag test only.

if you turn the key on and off 3x it will display DTC codes.

my truck is showing code P0602, and from what i have read it is no big deal and a software update fixes it.

i think being able to do that with the truck is pretty cool. all ive had is GMs before and i dont believe it was possible to pull codes or run a cluster test.

BigDogJeepin

My 2006 WIF light doesn't come on.....whole lotta hi-jacking going on here, though!

00Dog

What's the deal? Can we get some more 06's to check? I'm taking it in tomorrow morning. How could they make it that every bulb comes on except that one?

So true on the hi-jacking. I'm still getting the info I was originally looking for though.

Smokeman

On my 06 the WIF light does not come on when doing this check.

00Dog

Smokeman (and others),

Just want to confirm you're doing the full cluster test by holding the odometer butten down at key on and not just turning the key on as if starting the truck. Every single light comes on on my panel except WIF. This includes turn signals, all of the 4wd signals, trans overheat, etc.

ptgarcia

Just checked my '06 Megacab and no WIF light, but I do have some codes or something. When I hold down the trip reset button and turn the key to on, the display spits out C 447, S 116, and what appears to be . 281. Any idea what these mean?

Thanks.

Mopard

No WIF light for me ... if it helps. Kinda neat.

Mine displayed ... S 121, .282 and C447 in that order.

haha, my numbers are bigger than yours

BigDogJeepin

.281 and .282 are clearly your last breath alcohol test results............

Sorry for encouraging the hijack.

speakle

I have no WIF light either, what gives? Mine blinked out:
S 127
. 285
C447

vzdude

Here is some info from the instrument cluster portion of the service manual. It probably won't help your situation, as it looks like you have to have a scanner to diagnose it. More than likely those codes are from the CAN BUS system, due to a communication problem. I could have swore I saw a TSB somewhere for that, but anyhow........here's the info.........

OPERATION
The water-in-fuel indicator gives an indication to the vehicle operator when there is excessive water in the fuel system. This indicator is controlled by a transistor on the instrument cluster circuit board based upon the cluster programming and electronic messages received by the cluster from the Engine Control Module (ECM) over the Controller Area Network (CAN) data bus.

The water-in-fuel indicator Light Emitting Diode (LED) is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by the instrument cluster transistor. The instrument cluster will turn ON the water-in-fuel indicator for the following reasons:

Bulb Test - Each time the ignition switch is turned to the ON position the water-in-fuel indicator is illuminated for about two seconds as a bulb test.
Water-In-Fuel Indicator Lamp-On Message - Each time the cluster receives an electronic water-in-fuel lamp-ON message from the ECM indicating that there is excessive water in the diesel fuel system, the water-in-fuel indicator will be illuminated. The indicator remains illuminated until the cluster receives a lamp-OFF message from the ECM, or until the ignition switch is turned to the OFF position, whichever occurs first.
Actuator Test - Each time the cluster is put through the actuator test, the water-in-fuel indicator will be turned ON, then OFF again during the bulb check portion of the test to confirm the functionality of the LED and the cluster control circuitry.
The ECM continually monitors the water-in-fuel sensor to determine whether there is excessive water in the diesel fuel system. The ECM then sends the proper lamp-ON or lamp-OFF message to the ElectroMechanical Instrument Cluster (EMIC). For further diagnosis of the water-in-fuel indicator or the instrument cluster circuitry that controls the indicator, (Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING).

For proper diagnosis of the water-in-fuel sensor, the ECM, the EMIC, the CAN data bus or the electronic communication related to water-in-fuel indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

vzdude

OPERATION
The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter/water separator. As the water level in the filter/separator increases, the resistance across the WIF sensor decreases. This decrease in resistance is sent as a signal to the ECM and compared to a high water standard value. Once the value reaches 30 to 40 kilohms, the ECM will activate the water-in-fuel warning lamp through CCD bus circuits. This all takes place when the ignition key is initially put in the ON position. The ECM continues to monitor the input while the engine is running.

vzdude

I would think the codes COULD be from the sensor being either open or shorted, being the easiest thing. If you are'n in warranty, I would try disconnecting the sensor, disconnect the batteries, the hook everything back up besides the sensor and do the bulb check again. There will probably still be a code - because now the sensor is open, but the bulb may work? Other than that, you have to have a scanner .

BigDogJeepin

So has anyone determined whether the WIF light is supposed to light on a bulb test?

vzdude

YES!

dangmessagetooshort