ad8370w5000b

Auxiliary heater, diagnosis, troubleshooting

Type ad · topic 83.70 · version 0101 · 2003-06-16

Applies to: MODELS 970, 972, 974, 975, 976 with CODE (H60) "Eberspächer" D1 LP warm air auxiliary heater with CODE (H61) "Webasto" Air Top 2000 warm air auxiliary heater with CODE (H62) "Eberspächer" D3 LP warm air auxiliary heater '

Where it sits

Function group 3 Body › 83 Climate control › 83.70 Auxiliary/supplementary heater — Series 970 · Series 972 · Series 974 · Series 975 · Series 976

AD83.70-W-5000B

Auxiliary heater, diagnosis, troubleshooting

16.7.97

MODELS 970, 972, 974, 975, 976
with CODE (H60) "Eberspächer" D1 LP warm air auxiliary heater
with CODE (H61) "Webasto" Air Top 2000 warm air auxiliary heater
with CODE (H62) "Eberspächer" D3 LP warm air auxiliary heater

Auxiliary heater (ZHE) diagnosis, basic knowledge

AD83.70-W-2000B

a

Battery voltage 22.5-29.5 V.

b

The electrical system is checked in accordance with the vehicle's Operating Instructions and is in order.

c

When testing warm air auxiliary heaters with the Multimeter, ground must apply at pin 18 plug of the ZHE at pin 4 and at pin 1 terminal 30.

Troubleshooting

Complaint

Possible cause

Note

Remedy

Auxiliary heater switch S62 inoperative.

Open-circuit or short-circuit of cable from ZHE control module to auxiliary heater switch.

Auxiliary heater switch defective.

Check cables, plugs, connectors, fuses and electrical components for damage, correct connection, loose contact, corrosion, etc.

Check auxiliary heater switch.

Preselector clock S61 inoperative.

Open-circuit or short-circuit of cables from ZHE control module to preselector clock.

Preselector clock defective.

Check cables, plugs, connectors, fuses and electrical components for damage, correct connection, loose contact, corrosion, etc.

Check preselector clock.

Sooty combustion.

Combustion air/exhaust pipe blocked.

Fuel metering pump delivers too much fuel.

Deposits in heat exchanger.

Eliminate blockage.

Check fuel metering pump.

Eliminate deposits.

Referenced documents