80 The Interior Vehicle Heating Is Insufficient And The Engine Coolant Is Discolored (GROUP 80, NO. 23-12)

80 THE INTERIOR VEHICLE HEATING IS INSUFFICIENT AND THE ENGINE COOLANT IS DISCOLORED

TECHNICAL SERVICE BULLETIN

SERVICE INFORMATION

80 23 12 2062583/2 January 17, 2023. Supersedes Technical Service Bulletin Group 80 number 21-11 dated March 19, 2021, for reasons listed below.

Model(s)	Year	VIN Range	Vehicle-Specific Equipment
All Audi Vehicles	2012 - 2021	All	Not Applicable

CONDITION

Revision	Date	Purpose
2	-	Revised Warranty  (Updated Labor Operations)
1	03/19/2021	Initial publication

Customer states: 

Insufficient or uneven cabin heating performance from the HVAC system. The cabin heating may be slow to get warm.

TECHNICAL BACKGROUND

The symptom can easily be duplicated. The engine coolant may contain contaminants that are visually apparent. These contaminants can obstruct the coolant flow through the heater core and diminish the cabin heating capability of the HVAC system.

PRODUCTION SOLUTION

There has been a change in the coolant standard to G12 evo.

SERVICE

Diagnosis will reveal a drastic temperature difference between the inlet and outlet heater hoses to the heater core with the inlet being warmer than the outlet suggesting an obstruction in the heater core.

Risk of scalding due to hot coolant. The cooling system is under pressure when the engine is warm. Risk of scalding due to hot steam and hot coolant.

While there may be any number of causes for insufficient cabin heating, the subject matter covered in this TSB addresses only one possible cause. Should the symptom profile be inconsistent with the root cause described in this TSB continue diagnosis to find an alternative cause.

1. Examples of what the appearance of the discoloration of both the coolant as well as the coolant reservoir (Figures 1 - 4). This coolant contamination is not  engine oil or transmission fluid.
2. Clean and flush the cooling system using the cooling system cleaning set, part number G 052 525 A3 as follows (Figure 5):
3. Drain coolant when the engine is warm and the coolant thermostat is open according to the procedure in ElsaPro (Figure 6).
4. Flush the heat exchanger(s) with water in the opposite flow direction  . Do not exceed 2 bar of water pressure (Figure 7).
5. Blow the coolant out of the heat exchanger(s) in the opposite flow direction  (Figure 8).
6. Add 3.0 liters of cooling system cleaner 'S' and the balance of the fill with coolant (Figure 9). Perform bleeding procedure. Run the engine for 90 minutes with this mixture with the cabin heating on full hot and HI fan. If equipped, also set the rear HVAC unit to full hot and HI fan.
7. Drain the cleaning solution.
8. Add 3.0 liters of neutralizer 'S' and the balance of the fill with coolant. Perform bleeding procedure (Figure 10). Run the engine for 15 minutes with this mixture with the cabin heating on full hot and HI fan. If equipped, also set the rear HVAC unit to full hot and HI fan.
9. Drain the neutralizer solution.
10. Fill the cooling system with plain distilled water (Figure 11). Perform bleeding procedure. Again, set the cabin heating to full hot and HI fan. If equipped, also set the rear HVAC unit to full hot and HI fan. Run the engine at approximately 2000 rpm until the cooling fans activate. Continue to run the engine at this speed for an additional 3 minutes.
11. Drain the distilled water fill.
12. Repeat this rinse process an additional cycle (repeat steps 13 and  14).
13. Once again, drain the distilled water fill.
14. If the coolant expansion tank is still discolored after the cleaning process it must be replaced (Figure 12).
15. Fill the cooling system with coolant at the proper mix ratio of coolant and distilled water according to the procedure in ElsaPro (Figure 13). Perform bleeding procedure.
    NOTE: Do not reuse any of the cleaning and coolant solutions used during this process.
16. Replace the heater core only  in cases where normal cabin heating performance is not restored after performing this cleaning and flush procedure and the root cause is confirmed to be an obstructed heater core.

WARRANTY

Claim Type:	110 up to 48 Months/50,000 Miles. G10 for CPO Covered Vehicles - Verify Owner. If the vehicle is outside any warranty, this Technical Service Bulletin is informational only.
Service Number:	8023
Damage Code:	0016
Labor Operations:	Drain and fill cooling system (4 x drain, fill and bleed operations)	1938 17XX	See SRT with associated operations
	Empty and clear out heater core, fill and clean using cooling system cleaning set (4 cylinder engines)	8023 2999	160 TU
	Or
	Empty and clear out heater core, fill and clean using cooling system cleaning set ('V' and 'W' engines)	8023 2999	250 TU
	For vehicles that have a second heat exchanger: Empty and clear out heater core, fill and clean	8823 2999	100 TU
Diagnostic Time:	GFF - Checking and clearing fault codes included in existing labor operations	0150 0000	Time stated on the diagnostic protocol (Max 40 TU)
	Road test prior to the service procedure	0121 0002	10 TU
	Road test after the service procedure	0121 0004	10 TU
Claim Comment:	As per TSB 2062583/2

All warranty claims submitted for payment must be in accordance with the Audi Warranty Policies and Procedures Manual  . Claims are subject to review or audit by Audi Warranty.

REQUIRED PARTS AND TOOLS

Always check with your Parts Department and/or ETKA for the latest information and parts bulletins.
Part Number	Part Description	Quantity
See ETKA	Fasteners, Bolts, Nuts, and Screws as needed per the Repair Manual	See ETKA/ELSA
G052525A3	Cooling system cleaning set	01
See ETKA	Coolant	30 liters

Tool Number	Tool Description
T10007B	Analog Refractometer
VAS 6096	Cooling system charge kit
VAG 1274/X	Adapter

ADDITIONAL INFORMATION

All parts and service references provided in this TSB (2062583  ) are subject to change and/or removal.

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