Terminal connection diagram

Test steps

1. Replace ZW relay by a new one, or after removing the relay, measure the resistance directly between the winding contacts 85 and 86.
   R_Target = 285-310 Ω.
2. Open S2 plug connection.
   For steps 1-4, bring one test probe of the ohmmeter into contact with the vehicle ground. Measure resistance at contact 51 of cable 2.
   R_Target = 285-310 Ω.
   If R = R_Target, continue with 4.
3. S3 socket connection: Measure resistance at supply cable to winding start of the ZW relay (pin contact 86).
   R_Target = 285-310 Ω.
4. S3: Measure resistance at supply cable to winding end of the ZW relay (pin contact 85) and ground point. R_Target = 0 Ω.
5. If the central warning light burns in neither case, exchange light bulb.
6. Measure resistance between + and – cable ZW.
   With light bulb: R_Target = approx. 160 Ω
   Without light bulb: R_Target = ∞ Ω.
7. Check resistance of + and – cable ZW to vehicle ground. R_Target = ∞ Ω.
8. S3: Check resistance at ground cable of the ZW relay (pin contact 87). R_Target = 0 Ω.