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Test D22 - A4LD Trans

NOTE: Perform this test only when Code 86 or 89 is displayed or referred here by other chart or test procedure. To prevent replacement of good components be aware that the following non-EEC areas may be at fault:
Fig 1: A4LD Transmission Circuits
G120775
  1. Code 86 or 89: Circuit Identification. Code 86 indicates ECA did not see a voltage drop when the Shift Solenoid (SS) was activated. Possible faults are: SS resistance out of limits, SS circuit open or grounded or faulty ECA. Code 89 indicates ECA did not see a voltage drop when the CCO solenoid was activated. Possible faults are: Converter Clutch Override resistance is out of limits, CCO circuit open or grounded or faulty ECA. Enter this test step for KOEO codes. Verify codes match appropriate transmission solenoid circuit.
    TRANSMISSION SOLENOID CIRCUITS

    Solenoid Type ECA Signal Output Pin KOEO Code
    Converter Clutch Override (CCO) 53 89
    Shift Solenoid (SS) 3/4-4/3 52 86

    If any of the above codes are present, go to next step. If not, service other codes as necessary.

  2. Checking Resistance of A4LD Solenoid. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair if necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pins No. 37 and 57 and ECA signal output pin at the breakout box. If the resistance is 26 to 40 ohms, go to step 5). If resistance is not 26-40 ohms, go to next step.
  3. Check Continuity of Transmission Solenoid Harness. With key off, install breakout box. Leave ECA and transmission bulkhead connector (A4LD solenoids) disconnected. Set DVOM on 200-ohm scale. Measure resistance between test pins No. 37 and 57 at the breakout box and VPWR circuit pin of the harness connector at the transmission. Measure resistance between the ECA signal output pin No. 52 at the breakout box and SS pin of the harness connector at the transmission.
  4. Check For Shorts to Power or Ground of A4LD Solenoid Harness. With key off, install breakout box, leaving ECA disconnected. Disconnect transmission bulkhead connector. Set DVOM on 200K-ohm scale. Measure resistance between the ECA signal output pin and test pins No. 37 and 57 at the breakout box. Measure resistance between the ECA signal output pin and test pins No. 40, 60 and 46 at the breakout box and at chassis ground. If all resistances are greater than 10K ohms, go to next step. If any resistance is less than 10K ohms, repair short circuit, reconnect components and rerun QUICK TEST.
  5. Check VPWR Voltage to Transmission Solenoids. With key off, breakout box installed and ECA connected, set DVOM on 20-volt scale. Disconnect transmission bulkhead connector. Turn key on, leaving engine off. Measure voltage between test pins No. 37 and 57 at the bulkhead connector and chassis ground. If voltage is greater than 10.5 volts, repair or replace transmission solenoid as necessary. If voltage is less than 10.5 volts, replace ECA, reconnect components and rerun QUICK TEST.
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