Checking components and wiring
Check the cable between relay 2/82 terminal #3 and the broad flat terminal pin on the blue radio antenna amplifier in the left D-post. Check for an open-circuit according to Open-circuit, permanent faults . Check for a short-circuit to ground according to Short-circuit to ground, permanent faults .
Check the copper tongue (cable) between the blue radio antenna amplifier in the left D-post and the heating loops in the rear windshield. Check for an open-circuit according to Open-circuit, permanent faults . Check for a short-circuit to ground according to Short-circuit to ground, permanent faults .
Check the grounding of the heating loops via the white antenna amplifier in the right D-post against the ground terminal for an open-circuit according to Open-circuit, permanent faults .
Check the heating loops for an open-circuit according to Open-circuit, permanent faults . Take readings between the copper tongues (cables) in the left and right D-posts.
HINT: An open-circuit can only be detected if none of the heating loops are functioning.
If only some of the heating loops are defective, these can be identified by activating the heating for the rear windshield, then breathing on the rear windshield at each heating loop. The condensation will disappear more quickly at the heating loops that are functioning.
Remedy as necessary.
Other information:
- For further information about signals and other values, see Signal specification .
- To access the blue antenna amplifier (radio and TV antenna amplifier), see Windshield antenna and amplifier .
- To access the white antenna amplifier (TV antenna amplifier), see Windshield antenna and amplifier .
- To replace the rear windshield, see Removing the rear windshield .
- Fully functioning heating loops have a resistance of 0.41 ohms at 20°C. If the resistance is higher, one or more of the heating loops are defective.
Was a fault detected?
- YES
OKAY: Troubleshooting has been completed.
- NO
FAULT NOT FOUND: Troubleshooting has been completed.