2010 QX56 4WD warning light issue

[retho78]

For the past few days while driving the vehicle in 2WD, the 4WD warning light turns on and goes off, not flashing either and this happens randomly. I checked the battery and it was weak, CCA was 585 and it is rated at 710 and starting capacity at 75%, got it charged up and now it is up to 690 CCA and 95% starting capacity thinking that was the problem but no, the 4WD is still coming on now. Any ideas what could be the problem, relay / sensor / malfunction with the 4WD system? Where should I start?

Thanks in advance.

[marctronixx]

first i would see if any trouble codes at the obd port.

replace battery/get charge system checked.

could be a faulty mechanical component... worth a look see under the chassis...

[retho78]

I checked for OBD codes and nothing present. The charging system is good and battery is good and up to 98% starting capacity with 705 CCA. I did some online research and found about the relay going bad, the one by the passenger fender area and located by the side of the battery. I took it out and cleaned the connectors and swapped with the one right next to it, which is the same part. I will drive around for few days and see how it does.

Thanks.

[retho78]

Drove the vehicle around couple times today and the 4WD warning light has not come back ON. Keeping my fingers crossed that cleaning the connectors resolved this issue.

I will keep you posted if something changes.

[marctronixx]

that is the IPDM i think you are talking about. that sucker is a little gremlin! :p

if it is indeed the IPDM, you can use the fog lamp relay in a pinch to test/ get things going temporarily.

if its not the IPDM, its wise to have a spare in your glove box.

[retho78]

It is not the IPDM, the relays I'm talking about are the two that are located behind the battery, side of the inner passenger fender and close to the headlight. I believe one is for the rear air suspension ride and one is for the 4WD system, they both have the same part# 25237-EA000. After taking both relays out I notice some calcium build up around plastic casing of the wire connectors so I'm guessing it gets exposed to rain, car wash etc. So I cleaned them both and put some dielectric grease between the connectors, hope that will hold up for a while and so far no issues but will keep you posted if anything changes.

[marctronixx]

no worries. the IPDM is also located in that panel.

[retho78]

Just wanted to stop by and give an update, so far everything is working fine, no 4WD warning light.