Checking and adjustment of the CO2 emission value - ra83001401177x(1177)

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

A. With gas sensor, B. With CO2 tester, C. Adjustment of emission value Model 140 with auxiliary heater

Operation number of operation texts and work units or standard texts and flat rates: 83-091060, 83-091201

Fig 1: Checking Co2 Emission Valve

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Auxiliary heater	Switch on.
Exhaust emission test	Perform after approx. 5 min. operation
Test result	Compare with test and adjustment data.
Emission value	Correct if necessary.

TEST AND ADJUSTMENT DATA

Test at heater capacity	Battery voltage	Emission value vol.%
Full	approx. 11 - 12 V	10 - 13
Half	approx. 11 - 12 V	7 - 10

COMMERCIALLY AVAILABLE TOOLS

	Order number	e. g. manufacturer
Gas sensor,	CH 304	Dragerwerk,
hot air probe or	CH 213	Moislinger Allee 53/55
car exhaust probe	CH 214	D-2400 Lubeck 1
CO₂ tube 1-20 vol.%	CH 25101
CO₂ tester with intake device, exhaust gas probe, filter wool, replacement charge and sheet steel case	1500	Bruno Ihrig Technische Meβgerate D-6054 Rodgau-Dudenhofen
Angled screwdriver for allen bolt (5 mm)	2100-05	Hazet, Postfach 10 10 67/68 D-5630 Remscheid 1

Checking emission value with gas sensor

Switch on auxiliary heater at a coolant temperature display <40°C.
Break off both ends of the CO₂ tube.

Fig 2: Checking Emission Value With Gas Sensor
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Insert end of CO₂ tube with higher scale value into exhaust gas sensor.
Attach hot air probe or car exhaust probe to other end of CO₂ tube.
NOTE: In the case of the car exhaust probe, the second outlet (arrow) must be sealed off.

Fig 3: Locating Tube With Higher Scale Value Into Exhaust Gas Sensor
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
After auxiliary heater has been running for approx. 5 min., compress rubber bellows of exhaust gas sensor by hand and introduce hot air probe or car exhaust probe into the exhaust outlet.

Fig 4: Compressing Rubber Of Exhaust Gas Sensor
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Release rubber bellows and wait until chain (arrow) is taut.

Withdraw exhaust sensor and read off emission value.

Heating capacity	Vol.%
Full	10-13
Half	7-10

Adjust emission value if necessary, see C.

Fig 5: Releasing Rubber And Wait Chain

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Checking emission value with CO ₂ tester

NOTE: Measurements are performed using a special fluid which absorbs the CO₂ from the exhaust probe. The change in volume which occurs then is displayed in vol. %. The special fluid must be renewed every six months or after 300 measurements. Further information can be found in the operating instructions included with the tester.

The special fluid is corrosive - caution is required when handling and touching painted surfaces.

Switch on auxiliary heater at a coolant temperature < 40°C.
Before each measurement, rotate tester 180° in the vertical plane; the measuring fluid must flow completely through the hollow body of the unit.

Fig 6: Measuring Hollow Body Of Unit
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Return tester to initial position; measuring fluid runs back.
Remove protective cap from valve (arrow). Push down valve several times. This bleeds the unit.

Fig 7: Locating Return Tester To Initial Position
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Align the zero point of the scale with the fluid level.

Fig 8: Aligning Zero Point Of Scale With Fluid Level
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
After auxiliary heater has been running for approx. 5 minutes, insert exhaust probe into exhaust outlet.
Push rubber connector of exhaust probe firmly onto valve of tester and hold down for the entire duration of the measurement. This pushes the valve downwards. Keep the tester vertical.
With the other hand, press the rubber bellows 18 times. Then remove the rubber connector quickly from the valve so that the gas cannot escape.
Rotate tester 180° four times; at each rotation, the measuring fluid must run completely through the hollow body of the unit.

Fig 9: Pushing Rubber Connector Of Exhaust Probe Firmly Onto Valve Of Tester
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Position tester vertically and read off CO₂ value when the measuring fluid has settled.

Heating capacity	Vol.%
Full	10-13
Half	7-10

Adjust emission value if necessary, see C.
After completing the test, remove the exhaust probe. Bleed the tester by pressing the valve (arrow) and then push the protective cap onto the valve.

Fig 10: Locating Exhaust Probe

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Adjusting emission value

NOTE: One turn of the adjustment screw changes the emission value by approx. 0.5 vol.%.

Turning in = CO₂ value drops

Turning out = CO₂ value increases

Fig 11: Identifying Screw

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Remove front panelling in front left wheel arch.
Turn adjusting screw as required.
Check emission value again after auxiliary heater has been running for approx. 5 minutes.
If emission value cannot be regulated:
- Check function of fuel metering pump (83-1122).
- If combustion air blower operates but does not achieve the specified delivery quantity, replace combustion air blower (Removing and installing combustion air blower ).
- If ceramic web in heater is burnt out or coked, replace ceramic web (85-5772).
After completing the test, switch off the auxiliary heater and attach the heater cover (REMOVAL AND INSTALLATION OF OUTER PANELING ON DOORS AND FENDERS ).