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Active Check Control Unit

Disconnect plug to control unit. Test input signals at disconnected plug.

ACTIVE CHECK CONTROL UNIT TESTING

Pins (Wire Colors) Conditions (1) Specifications
1 & 9 (Vio/Gry) Ignition Key @ "R" (2) B+ volts @ No. 1 &
Ground (-) @ No. 9.
2 & 9 (Brn/Yel) Ignition ON Completes ground ckt & activates
central warning light "ZHL".
3 & 4 (N/A) N/A Pin No. 3 (-) & No. 4 (+). "OH" light
on some models only.
4 & 9 (Grn/Wht) Ignition ON B+ volts (+) @ No. 4 &
Ground (-) @ No. 9. Controls "15"
indicator light.
5 & 4 (Blu/Wht) Ignition ON Ground (-) @ No. 5 & B+ volts
@ No. 4. Controls "O2" light.
6 & 9 (N/A) N/A B+ volts @ No. 6 & Ground (-) @ No. 9
Controls "AB" positive (+) ckt.
7 & 4 (N/A) N/A B+ volts @ No. 4 & Ground (-) @ No. 7
Controls "AB" Ground (-) ckt.
8 & 4 (Brn/Vio) Ignition ON B+ volts @ No. 4 & Ground (-) @
No. 8. Controls "FS" signal.
9 & 15 (Brn) N/A B+ volts @ No. 15 & Ground (-) @
No. 9. Controls "31" ground ckt.
(1) B+ volts = battery positive voltage.
(2) Controls "R" indicator light.