Allroad Quattro V8-4.2L (BAS) (2004)
Radiator Hose: Customer Interest
A/C - Poor Heater Output/DTC P2181 Set
19 08 09
2009948/7
November 17, 2008. Supersedes Technical Service Bulletin Group 19 number 07-03 dated April 30, 2007 for reasons listed below.
Vehicle Information
01 Low heater output (DTC P2181)
Condition
Low heater output. DTC P2181 (Cooling system performance) may be stored in DTC memory.
Technical Background
Low heater output may be due to a sticking non-return valve in the hose from radiator to left auxiliary radiator. If the valve is sticking, the engine takes
too long to warm up when the outside temperature is below 32 degree F.
Production Solution
Not applicable.
Service
Check coolant flow as follows:
allroad
Figure 1
1. Check cooling system by clamping off coolant hose (Figure 1) between non-return valve and left auxiliary radiator.
2. With coolant hose clamped off, check engine warm-up performance.
3. If engine warms up faster when coolant hose is clamped off, install new coolant hose with non-return valve (Figure 1).
S4