Aircommand IBIS ROOFTOP CARAVAN, Technical Manual

Page 6

    with silicone.

    Please Note: If water “pools” around the airconditioner (ie. The roof has

   sagged around the airconditioner) then the caravan manufacturer should be 

   consulted.

4: In high humidity areas, condensation may occur on the underside of the evaporator tray 

above the inside plenum. See fig 10 and 24.

This usually is associated with running the unit on low speed for a prolonged period. Under 

these conditions use the high or medium speeds and avoid “auto”

As it will cause the inside fan to drop to low speed as the set point temperature is 

approached.

Later production is fitted with more insulation on the underside to alleviate this problem. 

Quote part No 8001056……..

12: Water drips from the inside plenum only when it rains.

       Check condition 11 point 3 above.

Water ingress could also be due to rain entering the canopy/chassis  

joint and not being able to drain away to the outside. Check the limber holes in the nose

of the chassis. Refer fig 9 and check that the two drain holes are clear in the evaporator area.

13:Unit does not turn on. No display lights on the flip down display.

Proceed to check the following in order.

1: Check circuit breaker is on and the van has power.

2: Unscrew the inside plenum (4 screws) and disconnect plenum from control cable via the 

4 pin plug. With a multimeter, check power at inlet junction block. 240V AC. If OK, shift 

multimeter to 12V DC range.

         Check voltage across the control cable conductors. See Diag 1  & 1A

         If the correct voltages are detected as per Diag 1, then suspect a break 

between this plug and the display module. Inspect plug pins. Disassemble the display and 

check the plug to board is OK. (see fig 23)  If the voltages can be detected right up to the 

display, replace display.

3: If the voltages cannot be detected at the breakaway plug, then suspect the problem to be in 

the main control board enclosure.

Remove the canopy from the unit. Isolate the power to the aircon.

Remove lid of the RHS enclosure to gain access to the control board.

See Fig 1, 2 & 3. Firstly check the fuse on the board. If this fuse is blown it 

may

indicate a fan motor fault. If the fuse is ruptured, replace with a M205 S/Blow 5A  20 x 

5. If the fuse blows again, start investigating for a faulty condenser, evaporator motor or 

R/V.

If the fuse is not an issue, and the serial no of the unit is below IBSA02177. Then one 

needs to investigate the power supply driving the main board. If the board is powered 

from a transformer see fig1, then power up the unit, remove the 2 pin white plug that 

connects the transformer to board and with a multimeter set to 12V AC, check output. If 

no output, suspect a faulty transformer. Replace with a SMPS  Part No 8001039……..

For units below serial no IBSA 03280 and above 02177, these units will be fitted with 

an external switch mode power supply. See fig 2.

Here again remove the 2 pin white plug from the SMPS to board, set 

multimeter to 12V DC and check output. Earlier SMPS’s had an adjustment pot see fig 

20. It is worthwhile adjusting this pot if there is no output. 

If the power supply is deemed faulty then replace part No 8001039……

If the power supply is outputting OK, then change the main board.

Units Serial no above IBSA 03280 will have a main control board

with the power supply integrated on it. see fig 3

If there is no voltage output at the control cable with the integrated version, change the 

control board.