[natetru]

I have 2003 rubicon. Bought in december. Wheeled probly 5 times. Found out last nite that flashing locker lites mean the arent engaged.....so went out and did quick look. My air pumps never even come on....unplugged relays and switched them, still didnt get pumps to come on....thanks for any info u can give me!

 

[RubiCobra]

Were you testing the pump's output at the axle or at the pumps themselves?

 

[Jerry Bransford]

Rubicon lockers can only be engaged when the tcase is in 4Lo. Maybe that's why your compressors weren't coming on.

 

[natetru]

I put in 4lo, tranny in low 1, turn on front and rear lockers. Both lights flash, rear flashes also when on alone....i never hear pumps come on at all

 

[RubiCobra]

Try putting the t case in 4lo, trans in neutral, set your parking brake, hit your locker switch, get up underneath and disconnect the air line coming out of the lil compressor and see if there is any air being moved. The compressors are very quiet as they are very low pressure.

 

[natetru]

Negative on air movement...thanks, keep me moving in right direction.

 

[RubiCobra]

Try testing the relays, which are in the underhood fuse box if memory serves. If that's working test for power at the compressor. If it has power and isn't working, you may need to replace it.

 

[RubiCobra]

Actually back up a sec, can you put your hand on the compressor itself and tell if it's running? I've never done this myself so I'm spitballing here.

Maybe it's running and not moving any air...

 

[Jerry Bransford]

A Rubicon compressor is fairly quiet but it's not that quiet.

 

[RubiCobra]

That's what I thought too but I didn't want to send the op on an electrical wild goose chase if the compressor was actually running

 

[natetru]

No running at compressor...no vibration or noise.....how do i check the relays? Thanks

 

[Scastlet614]

No running at compressor...no vibration or noise.....how do i check the relays? Thanks

Swap that relay with another relay in the fuse panel and see if it makes the compressor start up

 

[RubiCobra]

I'm thinking test the power at the compressor first. At the top of the compressor bracket there are 4 connectors. Two of these supply power to the compressors and two are for feedback sensors in the axles.

Off the top of my head I dont remember which is which but you can follow the wires. Disconnect these, power your locker switch and test with a multimeter.

 

[RubiCobra]

Swap that relay with another relay in the fuse panel and see if it makes the compressor start up

This too.

 

[RUBI 4 MY MRS]

Make sure fuse #24 is good. That powers the pumps through the relays. If good you can test the pumps by jumping between the #30 & #87 terminals in the relay sockets for each relay.

 

[natetru]

Thanks you guys...will do these checks asap!

 

[natetru]

Fuse is good...swapped relays, no dice....guess i will need to pull the pumps down and give them a look