Test L: Open Abs Relay
DTC C1185 is generated when ABCM recognizes zero voltage at all HCU solenoids when battery voltage is expected. Possible contributing conditions include a defective ABS relay, blown ABS (60-amp) or HEGO (10-amp) fuse, low pull in voltage at relay, defective ABCM or HCU.
- Check ABS Fuse (60-Amp) & AIR COND Fuse (15-Amp)
Inspect ABS (60-amp) fuse and AIR COND (15-amp) fuse. If fuses are okay, go to step 4) . If ABS fuse is blown, go to next step. If AIR COND fuse is blown, go to step 3) . - Check For Short In ABS Relay Black/Red Wire Circuit
Disconnect ABS relay. Measure resistance between ABS relay harness connector terminal No. 87 (Black/Red wire) and ground. See Fig 1 . If reading is greater than 10,000 ohms, replace ABS (60-amp) fuse and go to step 4) . If reading is less than 10,000 ohms, repair Black/Red wire, and go to step 10) . - Check For Short In ABS Relay White Wire Circuit
Disconnect ABS relay and ABCM. Check resistance between ABS relay connector terminal No. 85 (White wire) and ground. If reading is greater than 10,000 ohms, replace AIR COND (15-amp), and go to step 4) . If reading is less than 10,000 ohms, repair White wire, and go to step 10) . - Check Power Supply Circuit (Black/Red & White Wires)
Disconnect ABS relay. Turn ignition on. Check voltage between ABS relay terminal No. 87 (Black/Red wire) and ground, and between terminal No. 85 (White wire) and ground. See Fig 1 . Turn ignition off. If readings were greater than 10 volts, go to next step. If reading was zero volts, repair Black/Red wire and/or White wire and go to step 10) . If reading was 1-9 volts (insufficient voltage to pull in anti-lock relay), check battery and charging system. See appropriate GENERATORS article in STARTING & CHARGING SYSTEMS. - Check ABS Relay
Perform ABS relay component test. See ABS RELAY under COMPONENT TESTING. If ABS relay is okay, go to next step. If ABS relay is defective, replace ABS relay and go to step 10) . - Check Relay Coil Red/Yellow Wire Circuit
Install breakout box. Check resistance between breakout box pin No. 57 and ABS relay harness connector No. 86 (Red/Yellow wire). See Fig 1 . Check resistance between breakout box pins No. 57 and 60. If reading between breakout box pin No. 57 and relay connector terminal No. 87 is less than 5 ohms, and greater than 10,000 ohms between breakout box pins No. 57 and 60, go to next step. If readings were not as specified, repair Red/Yellow wire between ABS relay and ABCM, and go to step 10) . - Check Relay Power Outlet Circuit
Disconnect ABS relay connector and HCU connector. Check resistance between breakout box pin 30 and ABS relay connector terminal No. 30 (Yellow wire). Reading should be less than 5 ohms. Check resistance between breakout box pin 30 and ground (pin No. 60). Reading should be greater than 10,000 ohms. If readings were as specified, connect ABS relay and HCU connectors, and go to next step. If readings were not as specified, repair Yellow wire between ABS relay and HCU. - Check Hydraulic Control Unit (HCU) Circuits
Using a jumper wire, connect breakout box pins No. 57 and 60. Turn ignition on. Measure voltage between specified breakout box pin and ground (pin No. 60). See HCU CIRCUIT CHECK table. Turn ignition off. If all voltages are more than 10 volts, replace ABCM and go to step 10) . If readings were not as specified, go to next step.HCU CIRCUIT CHECKBreakout Box Pin No. Circuit No. (Wire Color) 4 923 (Gray/White) 8 920 (Light Green/Black) 9 922 (Pink/White) 15 921 Pink/Gray) 31 903 (Pink) 47 902 (Brown) 49 904 (Purple) 50 905 (Blue/Orange) - Check HCU Power Supply
Turn ignition off. Disconnect HCU connector C115. Turn ignition on. Check voltage between ground and terminals No. 3, 4, 5 and 12 of HCU connector C115. See Fig 3 . Turn ignition off. If all readings were greater than 10 volts, replace HCU and go to step 10) . If readings were not as specified, repair Yellow wire of affected circuit, then go to step 10) . - Verify Repair
Restore ABS system and connect all components. Clear DTCs. Perform DRIVE CYCLE TEST . Check for any DTCs. If SYSTEM PASS is obtained, repair is complete. If SYSTEM PASS is not obtained and if original DTC exists, go back to step 1) . If SYSTEM PASS is not obtained and a different DTC exists, see DTC TEST INDEX table.