H2 Troubleshooting

H2 Tech Bulletins

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Ignition Switch Problems

Monday night I drove a few miles through the city to a freeway entrance where I accelerated to merge with the flow of traffic.  I eased off the gas as I reached 70 mph.  Instead of shifting into overdrive, the truck slowed down. I accelerated again to 70 mph and feathered the throttle to try and get overdrive to kick in; no such luck.  For several miles I maintain 70 mph @ 3300 rpm; no increase in oil pressure, I can hear the engine working from the exhaust note; no matter what I did I could not get overdrive to kick in.  The Service Engine Light comes on steady.  I decide to get off the freeway and travel the streets to the house.  As I pull away from the stop sign the truck is working hard as it feels it is starting from 2nd gear.  Each sign or light is an effort, as it appears the truck has no 1st gear.  So there I am, The Service Engine Light is on and it appears I don't have 1st gear or Overdrive.

Tuesday morning I drive the truck to the dealership; The Service Engine Light is on steady but the transmission is working properly.  I traveled side streets plus the freeway trying to duplicate what happened the night before.  Upon arrival at the dealership they scanned the truck and find 1 Emission DTC and 4 Transmission DTCs.

Tuesday afternoon the dealership calls to let me know my truck is fixed. They found the Ignition Switch had shorted and was responsible for the conditions identified above.  The removed and replaced the ignition switch.

Sometimes this is also followed with or by itself the complaint of the key will not come out of the ignition

The reason the ignition switch was replace is because the switch supplies power to the transmission through the transmission fuse. This is not a short but an open circuit in the switch.

Cleanout H2 Roof Drains

Open the roof and look in each corner and you'll see 2 small holes. Clean away any large debris. The weep holes are not only in the front but in the rear also. Follow the rails to the rear and you'll locate 2 more.  It is best to use low air pressure 10 to 15 p.s. i. if you use tank pressure you could risk blowing the  rubber tubes off inside the door posts. What works well is a can of compressed air like you use to blow off your computer keyboard.

Highway Wind Noise

The sunroof guard is not the cause of the highway vibration. You need to reseal the outside A pillar molding; the black one.  They need to be attached to the windshield. The cross wind picks up the molding thay lays on the windshield and then slaps it down. Check it by seeing if you can get your fingers under it and lightly pull up from the windshield. I have been fixing that noise since the H2 came out, open country here, good cross winds at times. Never have seen the wind deflector cause the noise, last one in had taken the deflector off.