When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hummer H2For those who like a little more gleam to their Hummer, the H2 offers a similar rugged look as the H1, but as a lower cost, and with more added features, making it almost a massive luxury SUV.
@Hdog
Reading back, these are the points that come to light in order of importance:-
You say you have an Engine Warning light but didn't say what the fault code is, if your "Launch Elite bilateral scanner" cannot provide it get a Tech2 to read it, otherwise you're shooting in the dark. For example "C0563" is EEPROM checksum error and only a Tech2 will correct it, altogether there are 14 Air Suspension related DTC's you really need to know which one it is.
You didn't say if whether or not you get the message "SERVICE AIR SUSPENSION" so I'm assuming not which would be strange.
A Tech2 will also provide the Left & Right ride height sensor voltage values which will confirm if they are behaving correctly i.e. whether the new or old sensors are operating OK.
You didn't mention if you checked the exhaust-valve pipe is blocked or if the valve is working, again a Tech2 should be able to lower the suspension, if this fails it suggests there is a problem with the exhaust valve, DTC0660 for example.
BTW where are you located?
Okay here goes. Yes my service air ride suspension is on. I will try to attach the codes I got so you can see what the scanner is saying. I'm from Spartanburg South Carolina. I also just replaced the ride height sensors with the more expensive dorman brand hoping that would help. But nothing has changed. Can you recommend a tech2 scan tool then maybe compatible with my H2. I am having trouble understanding which one is the right one. Even though some say they will do what I am needing then come to find out they don't. So any suggestions on the scan tool would be deeply appreciated. The attachment shows the codes I found under air suspension. These codes came from the launch Creader. I hope they're correct and I'm not chasing a different devil. Thank you and I appreciate the time you're taking to keep me straight.
I got my tech2 scan tool. No still working on it. RR height sensor is reading 0'04 volts. Now I'm trying to figure out what that problem is coming from. Hopefully I can figure something out soon.
DTC C0631 should have been set if the Air suspension module senses a suspension sensor voltage below 0.3 volts or above 4.7 volts, was this the case?
You only mentioned the RR, is the LR OK?
The Tech2 also shows the "Height Sensor Current" which is typically around 21mA for both sensors together, what is the reading?
The sensors power lines are wired together as follows:-
+5V reference supply (NOT +12V!!!) from AS ECU Pin 3 via 16-Way chassis connector Pin-N Grey wire (circuit 3A) connecting to Sensor Pins-1
Low voltage reference (NOT CHASSIS!!) from AS ECU Pin 7 via 16-Way chassis connector Pin-R Purple wire (circuit 2D) connecting to Sensor Pins-3
You should see +5V between Sensor Pins 1 & 3 both sides, if the sensor current is about right both sensors probably have power, alternatively disconnect each in turn and check the current changes.
Measure the voltage between Pin-3 and Pin-2 with a multimeter, this should change as the sensor's position is adjusted
Sensor Pins-2 for each side (both Brown) are connected as follows:-
RR (circuit 3C) to female 16-Way chassis connector Pin-S then ECU Pin-4
LR (circuit 3B) to female 16-Way chassis connector Pin-P then ECU Pin-5
16-Way Chassis Connector Wiring
Possible faults:-
No connection of the RR sensor to AS ECU Pin 4, check the 16-Way possibly a corroded pin or broken wire to Pin S, inspect and/or measure
DTC C0631 should have been set if the Air suspension module senses a suspension sensor voltage below 0.3 volts or above 4.7 volts, was this the case?
You only mentioned the RR, is the LR OK?
The Tech2 also shows the "Height Sensor Current" which is typically around 21mA for both sensors together, what is the reading?
The sensors power lines are wired together as follows:-
+5V reference supply (NOT +12V!!!) from AS ECU Pin 3 via 16-Way chassis connector Pin-N Grey wire (circuit 3A) connecting to Sensor Pins-1
Low voltage reference (NOT CHASSIS!!) from AS ECU Pin 7 via 16-Way chassis connector Pin-R Purple wire (circuit 2D) connecting to Sensor Pins-3
You should see +5V between Sensor Pins 1 & 3 both sides, if the sensor current is about right both sensors probably have power, alternatively disconnect each in turn and check the current changes.
Measure the voltage between Pin-3 and Pin-2 with a multimeter, this should change as the sensor's position is adjusted
Sensor Pins-2 for each side (both Brown) are connected as follows:-
RR (circuit 3C) to female 16-Way chassis connector Pin-S then ECU Pin-4
LR (circuit 3B) to female 16-Way chassis connector Pin-P then ECU Pin-5
16-Way Chassis Connector Wiring
Possible faults:-
No connection of the RR sensor to AS ECU Pin 4, check the 16-Way possibly a corroded pin or broken wire to Pin S, inspect and/or measure
Non-functional sensor - swap out to prove.
Defective ECU - hope not.
Hope this info helps.
Left sensor seems to be reading good.I have some pictures of some readings from the scanner. I hope you they make sense.
your ignition 3/ battery monitor voltage is waaay too low. if your voltages are higher at the battery terminals then i would suspect corrosion or bad wiring on your power feeds.
your ignition 3/ battery monitor voltage is waaay too low. if your voltages are higher at the battery terminals then i would suspect corrosion or bad wiring on your power feeds.
I have power drain somewhere. My battery keeps dying. So I had it hooked up to a charger so I could get the information you saw.
still too low. should be reading what the battery voltage is. maybe thats the issue right there. check the wiring diagram where those power lines come from. and trace it back.
still too low. should be reading what the battery voltage is. maybe thats the issue right there. check the wiring diagram where those power lines come from. and trace it back.
After checking the into it. I found a post that mentioned the low voltage. It says it should come back up. I checked into that and checked it with the Hummer running and the voltage came up to 12+volts. Could all this be coming from the ECM ?
After checking the into it. I found a post that mentioned the low voltage. It says it should come back up. I checked into that and checked it with the Hummer running and the voltage came up to 12+volts. Could all this be coming from the ECM ?
Can you tell me why my compressor relay is off and how to turn it back on?
Can you tell me why my compressor relay is off and how to turn it back on?
There is not on/off control as such for the Air Suspension relay, it's handled by the AS Electronic Control Unit
However faced with the same problem I went through the challenging exercise of replacing the AS Relay but all to no avail. Finally I inspected the AS 16-Way IP connector gently tugging on each wire and one just pulled out.
Can you guess which one it was?
Note it was actually on the mating side (yellow wire) to the green one highlighted.
May not be the same issue, but its worth checking the 16-Way connector for broken wires and /or corroded pins
The 50A VSES/ECAS relay (under the hood) feeds just the A/S relay
