Testing the shift control solenoid A and B assembly consists of two basic tests.
The first is a multimeter resistance test of each shift solenoid that makes up the assembly.
The other test is a bench test in which you apply battery power from your Honda Civic's car battery to see if you can hear the solenoid valve move and make a clicking sound.
Both of these test are simple and easy and in this tutorial I'll show you how to do them in a step-by-step way.
Contents of this tutorial:
The following 2001-2005 Honda Civic automatic transmission diagnostic tutorials may be of help too:
- How To Test The TCC Solenoid (2001-2005 1.7L Honda Civic).
- Clutch Pressure Control Solenoid A And B (2001-2005 1.7L Honda Civic).
You can find this tutorial in Spanish here: Cómo Probar Los Solenoides de Cambio A y B (1.7L Honda Civic) (at: autotecnico-online.com).
Symptoms Of A Failed Shift Control Solenoid A And B Assembly
In case you're wondering, the shift control solenoid A and B assembly is located on the bottom front corner of your Honda Civic's automatic transmission.
To be a bit more specific, the shift solenoid assembly is bolted to the transmission housing under the clutch pressure control solenoid A and B assembly.
The symptoms of a bad shift control solenoid A and B assembly depend on which of the two solenoids has failed.
Here's a breakdown of the symptoms produced by each (when they fail):
Symptoms of a bad shift control solenoid A:
- P0753: Shift Solenoid A.
- P0973: Shift Solenoid A Electrical Short.
- P0974: Shift Solenoid A Electrical Open.
- D4 indicator light flashing.
- A/T transmission does not shift.
- Erratic shifting: shifts from 1st to 3rd.
- Erratic shifting: shifts from 1st to 4th.
- Erratic upshift: 1st to 2nd.
- Erratic upshift: 3rd to 4th.
- Fails to shift: stuck in 4th gear.
Symptoms of a bad shift solenoid B:
- P0758: Shift Solenoid B.
- P0976: Shift Solenoid B Electrical Short.
- P0977: Shift Solenoid B Electrical Open.
- D4 indicator light flashing.
- A/T transmission does not shift.
- Erratic shifting.
- Erratic upshift: 2nd to 3rd.
- Fails to shift: stuck in 4th gear.
TEST 1: Shift Solenoid A And B Resistance Test
The very first test that we're going to do (on the shift solenoid A and B assembly) is to measure each solenoid's internal resistance with your multimeter in Ohms (Ω) mode.
If the resistance of each control solenoid is not within specification, then your Honda Civic's shift solenoid assembly is defective and needs to be replaced.
If you do you find that the internal resistance of each solenoid is within specification, then your next step is to apply battery voltage to each one and see if they make a solid clicking sound.
In case you're wondering, shift control solenoid A gets battery voltage on the terminal labeled with the number 1 (see image 1 of 2). Shift control solenoid B get battery voltage on the terminal labeled with the number 2 (see image 2 of 2).
NOTE: Each solenoid gets Ground through the assembly's base.
Here are the test steps:
- 1
Place your multimeter in Ohms (Ω) mode.
Don't have a multimeter or need to upgrade yours, take a look at my suggestion: Abe's Digital Multimeter Recommendations (at: easyautodiagnostics.com). - 2
Unplug your Honda Civic's shift control solenoid A and B assembly from its electrical connector.
NOTE: This test is done on the shift control solenoid assembly's connector AND NOT on the engine wiring harness' pigtail connector. - 3
Measure the resistance between terminal labeled with the #1 and Ground and then between terminal #2 and Ground.
NOTE: Shift solenoid A and B are grounded by the solenoid assembly's case. If the solenoid assembly is still bolted to the transmission housing, you can Ground your multimeter's lead directly on the battery's negative (-) terminal. - 4
Your multimeter should read 12-25 Ohms for the resistance value of shift control solenoid A and shift control solenoid B.
Let's take a look at what your test results mean:
CASE 1: Resistance was between 12-25 Ohms for both shift solenoid A and B. This is the correct and expected test result and generally means that shift solenoid A is OK.
Although the shift solenoid A and B assembly passed this test, there's still one more we need to do, which is to manually apply power to each of the solenoids that make up the assembly to see if the make a clicking sound. Go to: TEST 2: Applying Battery Voltage To Solenoid A And B.
CASE 2: Resistance WAS NOT between 12-25 Ohms for shift solenoid A or B. Recheck your multimeter test connections and retest.
If you still don't get the correct resistance, then shift control solenoid A and/or B is bad and the entire shift solenoid assembly needs to be replaced.
This test result also confirms diagnostic trouble codes P0753 and P0758 correctly indicating the shift solenoid assembly is defective.
