STI Home
Diagnostic Manual, Body and Accessories,
Volume 4.1

 Printable version
LOCATION:    14.3a Heated Seats (HS)   >   14 Diagnosis - Complaint Related Diagnostic Chart


Diagnosis - Complaint Related Diagnostic Chart

Preparation for Test:


The switches (left/right) for the front heated seats are integrated into the Front HS Control Module (N25/5). The control module can only be replaced as a complete unit.
1. Review section 0, 20, 22, 23
2. Review following documents in WIS: GF00.19-P-1000A.. Also review ETM documents: PE91.00-P-1100B (model 170), PE91.00-P-1100D Models 208, 202) and PE91.00-P-1100A (model 210).
Complaint/Problem Possible cause Test step/Remedy 1)
Entire front seat (left and right) heater system does not function. Front HS control module (N25/5), voltage supply
23 1.0
Left front seat cushion and seatback heating does not function.
Front HS control module (N25/5), voltage supply
Left front seat cushion heater element (R13/1) and left front backrest heater element (R13/2)
23 1.0,
23 5.0,
23 6.0
Right front seat cushion and seatback heating does not function. Front HS control module (N25/5), voltage supply
Right front seat cushion heater element (R13/3) and right front backrest heater element (R13/4)
23 1.0,
23 7.0,
23 8.0
Indicator lamps in left front HS switch (N25/5s1) or right front HS switch (N25/5s2) do not function.
Seat heating does function.
N25/5s1 indicator lamps


N25/5s2 indicator lamps
Front HS control
module (N25/5).

Front HS control
module (N25/5).
Dimming of indicator lamps in left front HS switch (N25/5s1) or right front HS switch (N25/5s20) does not function. N25/5s1 dimming

N25/5s2 dimming
23 2.0, 3.0, 4.0

23 2.0, 3.0, 4.0
Illumination of indicator lamps in left front seat heater
switch (S51/1) or right front seat heater switch (S51/2) does not function.
N25/5s1 or N25/5s2 illumination 23 2.0, 3.0, 4.0
Front HS control
module (N25/5).
1) Observe Preparation for Test, see 22.