KHH29ECTransmitter/Initiator

Tyre pressure monitoring users’ guide 1. Introduction Depending on the complexity of the system fitted, the tire pressure monitoring (TPM) system, consists of the following units: • an electronic control unit (ECU) called 14RC • four 29EC initiator units mounted in the wheel arches • and four or five wheel sensors mounted in each of the tires. The system monitors the pressure and temperature within the tires and flags an alarm via an UHF radio link when the tire pressure falls below predetermined limits. The warning display forms part of the dashboard. Two types of system are available, termed high line and low line. In the low line system the 29EC initiators are not fitted and the wheel sensors are factory fitted in active mode. In this application the sensors transmit data routinely every three minutes whether the vehicle is being driven or not. The high line system uses the initiators to transmit a low frequency signal to the wheel sensors – this activates them and this forces them to transmit. The highline system provides a faster update rate from the sensor and can provide an earlier warning of problems. 2. Operation There are no user adjustable controls on the TPM system. All the information is communicated by the dashboard display. The display will have anywhere between two and six lamps depending on the vehicle model, these are TREAD (Transportation Recall Enhancement, Accountability and Documentation act) lamp, diagnostics lamp and four positional indicating lamps (identify actual wheel with the problem). The diagnostics lamp will light if there is a problem with the TPM system, the TREAD lamp typically comes on when any tire is 25% under inflated. When the TREAD lamp comes on, the user is expected to rectify the problem when it is safe to do so. TRW, model 29EC

Page: 1/2 Photographs module Photograph 1: Transmitter/initiator, top view Page: 2/2 Photographs module Photograph 2: Transmitter/initiator, bottom view

 TRW 2004 Product: 29EC 1.1. Technical description of apparatus 1.1.1. Block diagrams Refer to the block diagram in figure 5. 29EC is a simple amplifier driving a resonant choke that acts as a magnetic antenna. A signal provided at the input is boosted by the transistor stage and fed to a resistor, capacitor and the choke connected in series. The capacitor is chosen to tune out the inductance of the choke and the resistor limits the current. The choke is mounted off the PCB to increase the resulting magnetic field. The DC power supply comes from a switched output on the 14RC ECU. After a short stabilisation period a 125kHz. drive signal is transmitted. The drive signal is on-off keyed to transmit data to the wheel sensors.  TRW 2004 Figure 4: Block schematic of the system Tire SP301 TPM Transmitter Tire SP301 TPM Transmitter L F C o m m u n i c a t i o n ( t o S P 3 0 1 O p t io n a l ) R F C o m m u n i c a t i o n ( f r o m S P 3 0 1 ) L F C o m m u n i c a t i o n ( t o S P 3 0 1 O p t i o n a l ) R F C o m m u n i c a t i o n ( f r o m S P 3 0 1 ) Tire SP301 TPM Transmitter L F C o m m u n i c a t i o n ( t o S P 3 0 1 O p t io n a l ) R F C o m m u n i c a t i o n ( f r o m S P 3 0 1 ) Vehicle TPM Receiver LF Initiatior (optional) LF Initiatior (optional) LF Initiatior (optional) LF Initiatior (optional) Tire SP301 TPM Transmitter L F C o m m u n i c a t i o n ( t o S P 3 0 1 O p t i o n a l ) R F C o m m u n i c a t i o n ( f r o m S P 3 0 1 ) Spare Tire SP301 TPM Transmitter R F C o m m u n i c a t i o n ( f r o m S P 3 0 1 )  TRW 2004 Figure 5: Block diagram of 29EC initiator Buffer Filtering and signal shaping Amplifier Input from 14RC Antenna

Page: 1/1 Photographs module Photograph 3: Transmitter/initiator, interior view

Test report 99512130 based on: FCC Part 15 Subpart C, sections 15.209 (10-1-03 Edition) Transmitter/initiator TRW 29EC Report number: 99512130 Contents MAIN MODULE.......................................................................................................................................................3 1 I NTRODUCTION ...............................................................................................................................................3 2 P RODUCT ........................................................................................................................................................4 3 T EST SCHEDULE ..............................................................................................................................................4 4 P RODUCT DOCUMENTATION ............................................................................................................................5 5 O BSERVATIONS AND COMMENTS .....................................................................................................................5 6 S UMMARY .......................................................................................................................................................6 7 C ONCLUSIONS .................................................................................................................................................7 TEST RESULTS MODULE.....................................................................................................................................8 1 S UMMARY .......................................................................................................................................................9 2 E MISSION TESTS ............................................................................................................................................10 2.1 Field strength of intentional signal .....................................................................................................10 2.2 Field strength of unwanted emissions ( < 30 MHz) .............................................................................11 2.3 Field strength of unwanted emissions ( > 30 MHz) .............................................................................13 USED TEST EQUIPMENT MODULE.................................................................................................................15 PHOTOGRAPHS MODULE .................................................................................................................................16 ADDITIONAL INFORMATION MODULE .......................................................................................................23 This report comprises of five modules. The total number of pages exclusive of the pages enclosed in the additional information module is: 23 Page: 3 of 23 Main module Report number: 99512130 Main module 1 Introduction This report contains the result of tests performed by: Telefication bv Edisonstraat 12a 6902 PK Zevenaar The Netherlands Telefication complies with the accreditation criteria for test laboratories as laid down in ISO/IEC 17025:1999. The accreditation covers the quality system of the laboratory as well as the specific activities as described in the authorized annex bearing the accreditation number L021 and is granted on 30 November 1990 by the Dutch Council For Accreditation (RvA: Raad voor Accreditatie). The copyright of this test report is owned by Telefication bv and may not be reproduced except in full without the written approval of Telefication bv. Ordering party: Company name : TRW Automotive Electronics Address : Stratford Road Shirley Zipcode : B90 4GW City/town : Solihull Country : United Kingdom Date of order : 31 March 2004 Page: 4 of 23 Main module Report number: 99512130 2 Product A sample of the following product was submitted for testing: Product name : Transmitter/initiator Product category : Intentional radiators Manufacturer : TRW Automotive Electronics Trade mark : TRW Type designation : 29EC FCC ID : KHH29EC Emission designator : None Hardware version : -- Software version : -- Serial number : -- 3 Test schedule Tests were carried out in accordance with the specification detailed in chapter 6 "Summary" of this report. Tests were carried out at the following location: • Telefication, Zevenaar The sample of the product was received on: • 2 April 2004 Tests were carried out on: • 5 and 6 April 2004 Page: 5 of 23 Main module Report number: 99512130 4 Product documentation For production of this report the following product documentation was used: Description Date Identification Circuit diagram 29EC 20/06/03 59308347 Assembly drawing29EC 23/06/03 59308348 Solder paste 23/06/03 59308347 Printed wiring board 23/06/03 59308347 Fabrication drawing 23/06/03 59308347 Mother panel drawing 23/06/03 59308347 Solder mask (top) 23/06/03 59308347 Solder mask (bottom) 23/06/03 59308347 Top metal 23/06/03 59308347 Bottom metal 23/06/03 59308347 5 Observations and comments This product operates as part of a tire pressure monitoring system, as indicated below: As this product is to be certified separately - for repeatablilty reasons - the 125 kHz square wave from the receiver (RC14) was simulated by means of a pulse/function generator. The initiator (29EC) is specified for operation in the frequency range 83.33 kHz – 181.82 kHz. During testing, the function/pulse generator was set to 131.5 kHz, which frequency yielded the highest attainable RF-field level. 125 kHz receiver (14RC)initiator (29EC) in: 315 MHz out: 315 MHz tire pressure sensor 125 kHz Page: 6 of 23 Main module Report number: 99512130 6 Summary The product is intended for use in the following application area: Tyre pressure monitoring for automotive applications The sample was tested according to the following specification: FCC Part 15 Subpart C, sections 15.209 (10-1-03 Edition) Page: 7 of 23 Main module Report numbe…

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Page: 1/3 Photographs module Photograph 4: 10 m test set up, ( < 30 MHz) Page: 2/3 Photographs module Photograph 5: 3 m test set up, ( < 30 MHz) Page: 3/3 Photographs module Photograph 6: T est set up ( > 30 MHz)