Hyundai Repair: check engine light, malfunction indicator light, hyundai elantra

Question
i took my 2001 hyundai elantra (automatic trans) to auto advance and dtc codes p1529, p0715 and p0705 came up.  when i am driving and get to 3rd gear maybe 4th the light comes on and it feels like it downshifted or something like that.  do you think i just need to have input and output speed sensors replaced?  

Answer
this is what is said about the codes you have given me




Technical Service Bulletin Group
40 - Transaxle

Number

01-40-020

Subject
Date

Automatic Transaxle Range Switch Diagnostic Trouble Codes P0705, P0707 & P0708
07-2001

Model

Accent 1995-2001, Elantra 1992-2001, Excel 1986-1994, Santa Fe 2001, Scoupe 1991-1995, Sonata 1989-2001, Tiburon 1997-2001 and XG 300 2001



AUTOMATIC TRANSAXLE RANGE SWITCH DIAGNOSTIC TROUBLE CODES P0705, P0707, P0708
DESCRIPTION:

An improperly functioning range switch may result in the following conditions:

Diagnostic trouble codes:
P0705 - Range switch signal incorrectP0707 - Range switch - open circuitP0708 - Range switch - short circuit or multiple inputs
MIL (Malfunction Indicator Light) illuminated
Harsh P-D or P-R engagement shock
REPAIR PROCEDURE:
Check for DTC in both the Engine and Automatic Transaxle menus. If any of the above DTCs are found, go to Step 2.
Disconnect the connectors to the range switch and the TCM. Check for bent pins or pins not fully inserted into the connector. Repair as necessary. If no problems are found, go to Step 3.

Follow the repair procedure shown below:
DTC REPAIR PROCEDURE
P0705
Replace range switch

P0707

P0708


Drive the vehicle for at least two key-on to key-off driving cycles using the shift lever to select L, 2, 3, D and R. If the DTC does not reset, return the vehicle to the customer. If the DTC returns, go to Step 5.
Repair or replace the wiring harness between the TCM and the range switch.
PARTS INFORMATION:
MODEL PROD. DATE PART NUMBER PART NAME
1999-2001 Sonata
980914-
42700-39050
Range Switch

2001 Elantra
000701-

2001 Santa Fe
000701-

2001 XG300
000701-

1997-2001 Accent
970501-
45956-28010

1996-2000 Elantra
951117/000630

1997-2001 Tiburon
960701/010630

1995-1997 Accent
940901/970201
45956-22600


WARRANTY INFORMATION:
MODEL OPERATION OP CODE OP TIME OP QTY NATURE CODE CAUSE CODE
1999-2001 Sonata
Replace range switch
42700R00
0.4
1
*N69
**C15

2001 Elantra

2001 XG300

2001 Santa Fe
0.6

All
Scan tool operation
42700RP0
0.3


MODEL OPERATION OP CODE OP TIME OP QTY NATURE CODE CAUSE CODE
1995-2001 Accent
Replace inhibitor switch
45900R00
0.5
1
*N69
**C15

1996-2000 Elantra
45900R00


1997-2001 Tiburon

0.6

All
Scan tool operation
42700RP0
0.3



*N69: Warning light on


**C15: Poor contact and short, open circuit