Instruction Manual

Chapter 7
Best Practices: Installation and
Troubleshooting
This chapter covers the Motorola Solutions recommended vehicle installation practices that can
address or prevent many issues.
• Radio circuit damage due to overvoltage condition.
• Radio/Accessories "lock-up".
• Radio/Accessories change state/lock-up when radio PTT is depressed.
• Radio powers up in the FL 01/90 state (general communication error code).
• Radio intermittently resets.
• Radio loses secure key.
• Transmit audio distortion on motorcycle radio when engine is running.
• Keypad buttons become inoperative for motorcycle radios when engine is running.
• Alternator whines when transmitting with engine running.
• Radio/Accessories turn themselves on/off.
7.1
Checking the Wiring of Ignition and Radio Ignition Sensing
• If it is required to turn the radio on and off using the ignition sense switch, in addition to the control
head on/off switch, connect the ignition sense lead to the accessory terminal from the ignition switch
(usually in the vehicle fuse panel under accessory or radio).
NOTICE: Motorola Solutions recommends protecting or isolating the radio ignition sense
input from voltage spikes more than +/- 40 VDC. Such spikes can be hundreds of volts in
amplitude and are common in larger vehicles (for example utility trucks and buses),
especially when the source is common to a solenoid coil. A triggerable oscilloscope is
required to determine the existence of such spikes as most voltmeters cannot measure in
short duration (< 1 ms). If the condition of the intended ignition sense source is unknown,
Motorola Solutions recommends isolating the source from the radio with a relay or the use of
a suppression diode wired between the source and ground. Any high current suppression
diode (MR2535) with a breakdown voltage of between 18 V and 40 V would suffice. A
suitable diode kit is available from Motorola Solutions parts, kit number HLN6325_.
• If it is required to have the radio power up only using the control head on/off switch, then connect
the ignition sense lead directly to the positive terminal of the battery. The ignition sense will always
be ignored and a re-wiring is necessary in the future if the operator chooses any ignition sense CPS
setting.
MN005720A01-AB
Best Practices: Installation and Troubleshooting
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