Hummer H1 Service Manual page 317

5-118 Transmission/Transfer Case
Step
7 Repeat the procedure in step 5. Drive the vehicle under
the following conditions:
• The transmission is in D4.
• The TCC is engaged.
• The APP angle is 12-70%.
Are the results the same as in step 5?
8 Refer to 4L80-E System Diagnosis Table, Slipping
TCC.
Did you find and correct the problem?
9 1. Remove the transmission oil pan. Refer to Trans-
mission Oil Pan Removal in 4L80-E On-Vehicle
Service.
2. Inspect for contaminated fluid and excessive mate-
rial in the pan.
Is the fluid or the pan contaminated?
10 1. Inspect the 1-2 SS Valve for contamination or dam-
aged seals.
2. Inspect the 2-3 SS Valve for contamination or dam-
aged seals.
Did you find a problem?
11 Inspect the following components for contamination or
sticking:
• The 1-2 shift valve.
• The 2-3 shift valve.
• The 3-4 shift valve.
Did you find a problem?
12 In order to verify your repair, perform the following
procedure:
1. Select DTC.
2. Select Clear Info.
3. Operate the vehicle under the following condi-
tions:
• Drive the vehicle in 4th gear, with the TCC com-
• The APP Angle is 12-70%.
• The PCM must see a slip of -25 to +30 RPM for
4. Select Specific DTC. Enter DTC P1870.
Has the test run and passed?
DTC P1870 Transmission Component Slip (Cont'd)
Action
manded ON.
greater than 1 second.
___________________________________________
Value
140-500 RPM
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—
—
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Yes No
Go to Step 9 Go to Step 11
Go to Step 12
—
Go to 4L80-E
Unit Repair Go to Step 10
Go to Step 12 Go to Step 11
Go to 4L80-E
Go to Step 12 Unit Repair
Begin the
diagnosis
again. Go to
System OK Step 1.
®